as fears of a lockdown promote panic buying across the chinese capital. for the first time, black women artists from britain and the united states win awards at the prestigious venice biennale. of course it's an enormous accolade, but i also think why is it taking so long? it should have happened before now. hello, welcome to the programme. the world's richest man, elon musk, has bought twitter for $41; billion. twitter originally rejected the offer, but its board has now advised shareholders to accept it. mr musk is an avid tweeter and he claims the site will perform better under private ownership. our technology correspondent james clayton reports. elon musk usually tweets cryptic messages, but there was nothing cryptic about his reaction to the news that twitter had accepted his offer. but people here in silicon valley are rubbing their eyes with disbelief. there will�*s richard mann now the owner of one of the most influential social media platforms —— the world's richard mann. twitter isn't the most used social media site in the world, but it is usually influential. world leaders like emmanuel macron and borisjohnson are all on it. when it comes to news generation, twitter has no comparison. but for years people, particularly on the right, they twitter stifles free speech. twitter has been criticised, particularly from the right, it is stifling free speech. donald trump's sensational lifetime ban from the platform is held up as a seminal moment, a sitting president's megaphone removed by big tech. elon musk says he wants to bring back free speech to the platform. the problem is, though, unfettered free speech can get very ugly, very quickly, when it comes to social media. h0 quickly, when it comes to social media.— quickly, when it comes to social media. no matter who owns or runs _ social media. no matter who owns or runs twitter, - social media. no matter who owns or runs twitter, the - owns or runs twitter, the president has long been concerned about the power of large social media platforms, the power they have over our everyday lives, he has long argued that tech platforms must be held accountable for the harms they cause. mr be held accountable for the harms they cause. mr musk will now have _ harms they cause. mr musk will now have to _ harms they cause. mr musk will now have to deal— harms they cause. mr musk will now have to deal with _ harms they cause. mr musk will i now have to deal with movements like qanon, this campaigns, and hate speech. the danger is that we do, without moderation, becomes poisonous. but for now elon musk is rejoicing. twitter is now his personal plaything. he is the new undisputed king of twitter. james clayton, bbc news, san francisco. we can now speak to evan greer, who's director of digital rights group fight for the future. thanks for talking to us. the world has already been having a conversation about the amount of power that social media platforms wield. how do you think elon musk might handle the responsibility that comes with this power? you the responsibility that comes with this power?— the responsibility that comes with this power? you know, i think that's _ with this power? you know, i think that's a _ with this power? you know, i think that's a great _ with this power? you know, i think that's a great question | think that's a great question and one that no—one really knows the answer to. frankly, including elon musk. he is not an expert in content moderation and, frankly, his public comments on the topic make it clear that he hasn't thought about it much beyond of kind of i like free speech, free speech is good. and i like free speech as well, i'm a free speech activist, and elon musk is right about one thing, is that free speech is in danger, but the reges man in the world simply purchasing a platform that millions of people depend on and then changing the rules to his liking is not the way to save free speech. we need policies to ensure that everyone has real choices when they go online so they can pick a social media platform that has content moderation and privacy practices that work with them, and their communities. that is how we preserve free speech for the future. ., , ., preserve free speech for the future. , ., ., , ., future. those two ideas are difficult to _ future. those two ideas are difficult to get _ future. those two ideas are difficult to get right - difficult to get right together, free speech but also online safety. what options does elon musk have the doing better than twitter has done so far? i, better than twitter has done so far? ., ~ ., ~' better than twitter has done so far? ., ~ ., ~ ., i, i, far? you know, think again what we need is _ far? you know, think again what we need is more _ far? you know, think again what we need is more control- far? you know, think again what we need is more control for- we need is more control for users. we can't be in a world where content moderation decisions are made at the whim of billionaires. we need content moderation decisions to be made through the lens of human rights to ensure free expression for the most number of people possible... but expression for the most number of people possible. . ._ of people possible... but who should be _ of people possible... but who should be making _ of people possible... but who should be making those - should be making those moderation decisions? someone has to? , �* moderation decisions? someone hasto? , ~ has to? exactly. and those moderation _ has to? exactly. and those moderation decision - has to? exactly. and those | moderation decision should has to? exactly. and those - moderation decision should be made transparently and democratically. ideally, social media would be structured in a decentralised manner with those decisions are made by many people together and where users have control so that you can create a community for you and your friends where there are perhaps a very loose rules, but you could also join a perhaps a very loose rules, but you could alsojoin a much larger —— larger community with the rules are stricter but you know what you're getting into and you know what you have agreed to, this really comes down to use a choice which is why we need policies like anti—trust legislation to crackdown on big tech monopoly power so that people have those choices, have those options. we see a lot of people are they saying i'm going to leave twitter, we need a world actually have somewhere to go, that's why we need lawmakers to act, not billionaires. mi act, not billionaires. all ri i ht, act, not billionaires. all right, thank _ act, not billionaires. all right, thank you - act, not billionaires. all right, thank you very much, evan greer, director of the digital rights group fight for the future.— digital rights group fight for the future. thanks for having me. the russian foreign minister, sergei lavrov, has again suggested there's a danger of the conflict with ukraine leading to a third world war, but he said he expected it to end with a peace agreement. mr lavrov said nato was in effect engaging in a proxy war with russia, and that weapons delivered to ukraine from the west would be, what he called, legitimate targets. five train stations were struck by russian missiles in western ukraine on monday. the railways have become a key target for russian forces, as they're crucial for both bringing in supplies and evacuating civilians. meanwhile, unrelenting russian attacks continue in the eastern donbas region. there's been fighting there since 2014, between ukrainian troops, and separatists, backed by moscow. russian artillery has been targeting towns and cities, where mainly civilians have been sheltering in basements, short of food and water. our defence correspondent jonathan beale has travelled close to the frontlines. birdsong explosion the first sounds of spring, now drowned out by heavy shelling. in eastern ukraine, their battered flag still flying, but signs of life are vanishing fast, in the face of a renewed russian offensive. russia is making small gains, but creating widespread chaos and devastation, right across the region. most have already fled the towns and cities of the donbas. it's the few, like valentina, who've stayed behind. we found her trying to find food, during a lull in the fighting. translation: of course it's dangerous. _ everybody is scared. now we are even afraid of silence. you never know what will happen next. this is now her home. lysychansk has become an underground city. she shares a dark, dank shelter with another 50 people. they say they're running out of clean water and food, and some don't even care which side is winning. translation: my brain hurts. two idiots are fighting, two old men. all of them are guilty. all of them. distant bangs but there is no peace from the constant barrage of artillery. it's becoming yet another russian war of attrition. they're trying to break ukrainian forces along a front line that stretches for 300 miles. we have bomb attacks, rocket attacks every day. every day, every time, every day, every hours, all day. if we lose, lose not only ukraine, lose all world. and your countries, and other countries, too. here, they're still relying on mostly old soviet weaponry. they proudly show off their one british—supplied anti—tank missile, the nlaw. they've already used the other one to destroy a russian tank. we need that weapon - for our freedom, for a win, for that war. we need that weapon. and when we have more of that weapon, war is ending. - do you have enough of them? that position? yeah. this position? no. ukrainian forces have been holding the line here since 2014 against russian—backed separatists. they're still holding the line, but this time against the russian army. and what has been sporadic fighting over the last eight years has now turned into a full—blown war, and they are being pounded by russian artillery. this war is grinding down life in the donbas. deserted towns and cities, slowly being destroyed, as we travel through the region, from lysychansk to slovya nsk, to lyman in the north. the only certainty — this will be costly and brutal for whoever wins this war. jonathan beale, bbc news, eastern ukraine. the businessman and philanthropist osman kavala has been sentenced to life in prison without parole in turkey after being found guilty of attempting to overthrow the government. the ruling was met with boos from a packed courtroom. human rights groups have condemned it as a travesty of justice. with me is our news reporter mark lobel. what is the significance of this verdict?— what is the significance of this verdict? this is added rocket fuel _ this verdict? this is added rocket fuel to _ this verdict? this is added rocket fuel to the - this verdict? this is added | rocket fuel to the concerns that people have had about the independence of the judiciary of turkey ever since the failed coup against president oda warne and coup against president 0da warne and 2016 were judges have been a brain drain from the judiciary, those who remain there seem to be working under a climate of fear, this is the view of one campaign outside the court in istanbul. deeply shocking and i think a very defiant decision which, of course, doesn't come from this court, it comes from the palace and this has been a political trial from start to finish. it is a shame trial, we call it, because _ is a shame trial, we call it, because there is no evidence. -- shame _ because there is no evidence. —— shame trial. domont has been consensus 2013 when there are anti—government rotors spread throughout turkey and they looked at who financed those process and they have been putting the blame on civil society, branding them agents of, in their words, society, branding them agents of, in theirwords, hungarian born george soros, ed culminated in a court case on monday in istanbul was 70 minutes got 18 years ease, but a particular defendant, the one you mentioned at the beginning, 0sman kavala, a 64—year—old philanthropist, having spent four and a half years without a conviction behind bars has now been sentenced to life in prison without parole. he denies all the charges and his response just before he got that sentence was that this is an act of assassination by use of the judiciary. so an act of assassination by use of the judiciary.— of the judiciary. so we have heard, of the judiciary. so we have heard. for— of the judiciary. so we have heard, for instance, - of the judiciary. so we have heard, for instance, from i of the judiciary. so we have i heard, for instance, from that campaign are there to dissatisfaction with the verdict. —— the dissatisfaction. and what can be done about it and can human rights campaigners expect the international community to exert anything?— exert anything? the international - exert anything? the - international community is exert anything? tie: international community is in a bind because they need turkey's help on a number of fronts, as an example as a mediator between ukraine and russia. the day of that result the un secretary general, antonio guterres, was in town meeting the president of turkey. so you can see how that can make it difficult for them to criticise what turkey has done. nonetheless, six months ago a letter was written by ten western diplomat saying that he should be released, the philanthropist should be released, those diplomats were nearly expelled at the time. america has continued as criticism. with that in the wake of this result that they are deeply troubled and disappointed and have again called for the release of this philanthropist. there is another issue here, the european human rights body, of which turkey is a member, has said that there is a lack of evidence against the philanthropist and he should be released. that was a ruling made some time ago and turkey is now risking being kicked off it. at the moment, some say turkey has failed a litmus test of the rule of law there. ibiiiii of the rule of law there. all ri i ht, of the rule of law there. all right. mark _ of the rule of law there. all right, mark labelle, thank you very much. stay with us on bbc news. still to come: the winning black female artists at the centre of this year's venice art biennale. nothing, it seemed, was too big to withstand the force of the tornado. the extent of the devastation will lead to renewed calls for government help to build better housing. internationally, there have already been protests. sweden says it received no warning of the accident. indeed, the russians at first denied anything had gone wrong. only when radioactivity levels began to increase outside russia were they forced to admit the accident. for the mujahideen, the mood here is of great celebration. this is the end of a 12—year war for them. they've taken the capital, which they've been fighting for for so long. it was seven o'clock - in the morning on the day when power began to pass from the minority to the majority. - when africa, after 300 years, reclaimed its last white colony. - this is bbc news, the latest headlines: elon musk, is set to buy twitter — in a joint statement, the two sides said they wanted to make the social media platform better than ever. the russian foreign minister, sergei lavrov, says nato is in effect engaging in a proxy war with russia, and that weapons delivered to ukraine from the west would be what he called legitimate targets. the authorities in beijing have announced they're expanding a mass—covid testing campaign to another ten districts after a sharp rise in cases in china's capital. people have been stocking up on food, as fears grow that the city could be locked down. millions of residents in shanghai are still in the middle of a lockdown that's lasted for more than a month. i'm joined now by christian petersen—clausen, a documentary filmmaker living in shanghai. he has been locked down since first april. thank since first april. you for talking to us. it is thank you for talking to us. it is almost a month of done for you now, what has it been like? it's been (speaks indistinctly), quite frankly, mainly because of the length of the lockdown. it was initially announced to be a 5— day lockdown and then extended indefinite and the communications from the government and local district has been that "you need to be case free for seven days to go outside of your building and another seven days to go outside into the city. however since every large apartment complex, in my case we haven't made it two days without a case or multiple cases. ibmd made it two days without a case or multiple cases.— or multiple cases. and we've seen reports _ or multiple cases. and we've seen reports of _ or multiple cases. and we've seen reports of green - or multiple cases. and we've| seen reports of green fencing or people being held in one place until there are no infections. can you just explain how this works in practice, what you've seen of it? ~ practice, what you've seen of it? . ., , practice, what you've seen of it? ~ ., , , ., , it? we have seen these mobile reen it? we have seen these mobile green fences — it? we have seen these mobile green fences go _ it? we have seen these mobile green fences go up _ it? we have seen these mobile green fences go up in - it? we have seen these mobile | green fences go up in shanghai. (speaks indistinctly) members who have seen them go up outside of entrances. again, we don't know why they are going up, this could be because people inside of those buildings are simply fatigued by the almost daily covid testing and refusing to come out and being isolated or it could be because people have walked out or it could be for a different reason. again the communication is quite terrible when it comes to that. what happens if you test positive is you are taken away to either a hospital or there are requisitioned office buildings now or sports stadiums, venues where they put beds inside and you are staying there basically and getting your care right there. ., , ., and getting your care right there. ., ,, , and getting your care right there. . i. , ., and getting your care right there. . , ., ., there. have you been out at all? are _ there. have you been out at all? are you _ there. have you been out at all? are you able _ there. have you been out at all? are you able to - there. have you been out at all? are you able to go - there. have you been out at| all? are you able to go out? how are you getting access to food and other supplies? food is a real concern _ food and other supplies? food is a real concern here. - food and other supplies? food is a real concern here. your. is a real concern here. your usual delivery apps are out of commission because the restaurants and shops and supermarkets are closed, so evenif supermarkets are closed, so even if you did initially not believe this lockdown was going to last five days but was going to last five days but was going to last five days but was going to last longer and you stocked up to last longer and you stocked up for a week or two, very quickly you are running out. there are limited supplies coming in from local districts, from government, but it doesn't mean enough, a box of vegetables every four or five days if you are lucky, or in a less well—organised area, it might be less. so what we do here, the entire building has created a group chat here and we place large orders. for instance, 50 boxes of red. and we divide them up amongst neighbours. that way we can convince the very few businesses that are still open, that are still either legally delivering or sneaking out to come to us to bring us food. that is quite a difficult situation there but thank you very much for taking the time to tell us about it. the defamation trial betweenjohnny depp and amber heard has started its second week in the us state of virginia. the hollywood actor is suing his ex wife for an article she wrote in which she described herself as a victim of domestic violence. so far the testimony has laid bare their violent fights, drug use and vicious words to each other. on monday, the court was played audio recordings of the couple's arguments. 0ur correspondent david sillito has the latest. today's evidence was dominated by audio. the couple, during the brief and very argumentative marriage, had taken to recording one another and today, a whole series of snippets of arguments were played tojohnny depp. in one of them, amber heard says that johnny depp beats the "expletive deleted" out of her. another, can you put your cigarettes out on someone else. and a comment from johnny depp where he talked about walking away before there was a bloodbath. all of which johnny depp bloodbath. all of whichjohnny depp said was either not to be taken literally, was an exaggeration or out of context. and there was also conversation from after the moment amber heard first said she was suffering domestic violence. after they had filed for divorce, they were discussing how to row back on all of this, how to row back on all of this, how to row back on all of this, how to come back to some sort of settlement and amber heard is heard saying, well, her credibility was at stake here, and she asked the question, if he is going to say he is a victim of domestic violence, who would actually believe him? the british artist sonia boyce has won the top prize, the golden lion at the venice art biennale which hasjust opened. she had already made history by being the first black woman to represent britain at the international art exhibition. our culture editor, katie razzall met sonia boyce in venice. the british pavilion at the venice art biennale has been transformed to the sound of five black female musicians. it's a hugely noisy, but hopefully joyously noisy experience. sonia boyce's work here, called feeling her way, is the latest stage in a wider project that tells the stories of black women singers and musicians. you are the first black female artist to ever represent britain. i wonder what you feel about that. um, i mean, of course it's an enormous accolade. but i also think, why has it taken so long? i mean, there are so many brilliant british female black artists out there. it should have happened before now. it's her time in the sun now. with a golden lion for the show, she's joined the likes of other famous british names, bridget riley and henry moore amongst them, to the very top biennale prize. boyce had this message. there's a longer arc of people that we need to keep saying, they're here. for more than a century, the world's most high profile art exhibition has centred around men. not this year. close to sonia boyce's pavilion, america's has a new temporary thatched roof, and an exhibition courtesy of simone leigh, the first black woman to represent the us here. they wanted to start this part of the show with this monumental artwork. simone leigh won the other golden lion prize for this 16 foot bronze sculpture at the central biennale show, curated by cecilia alemani. of the 213 artists featured in what's called the milk of dreams, between 80% and 90% are female. i wanted to give the stage and the platform to many amazing, wonderful artists who also happen to be women. and why has it taken so long, do you think? because we still live in a very sexist society, and it's very, very hard to advance. advance is happening in scotland's exhibition. this tapestry looks at slavery and the stories we're told. the artist, alberta whittle, is the first black woman to represent scotland in venice. i think the world's more ready to accept women artists, possibly. black women artists, i don't know. i'd like it if people weren't so scared to work with ideas of race or to kind of open up these conversations. but change is afoot here, certainly when it comes to whose art gets a place on the wall. katie razzall, bbc news, venice. sta rs of stars of the pop peeled dish television series downton abbey have hit the red carpet for the world premiere of the franchise's latest film, a new era as the family travels to the south of france. hugh bonneville said audiences should come along to the cinema and have fun. i should come along to the cinema and have fun.— and have fun. i fortunately felt incredibly _ and have fun. i fortunately felt incredibly privileged i and have fun. i fortunately| felt incredibly privileged to be working and enjoyed the job much more after the experience of what the world had been going through and i think experience is a tonic at a time when we need to escape —ism and its pure entertainment this film, were not trying to change the world are any great messages, just sit back and have fun. you can reach me on twitter — i'm @kacungira. hello. if it's rain you're after, you won't find any substantial amounts in this forecast. we were on monday teased by a few showers out there that only produced a few millimetres of rain here and there and they are not a sign of things to come. this weak weather front in scotland in northern england will squeeze out a little light and patchy rain on tuesday. but this is the main weatherfeature building in for the rest of the week and looks like for the rest of the month too. high pressure right across us, keeping things largely dry and settled, with a chance, though, it's on the cool side out there. a the touch of frost over the next few mornings. for tuesday mornings, across parts of southern scotland, northern and eastern england. the far northeast of scotland brightens up a touch. these areas seeing some of the higher temperatures, warmest near 17 degrees, but feeling quite cold through eastern scotland and northeast england, especially with this onshore breeze. any showers that have developed along with the cloud will melt away overnight and into wednesday morning. we keep some cloud though across eastern—most parts here. the chance again of a touch of frost looks to be on wednesday in parts of scotland and northern england. then on wednesday, it does look as if that area of high pressure moves right in to be a mainly dry day. where you start with cloud in the east, it mayjust thin and break in places. where you start elsewhere was sunshine, some clouds going to build, but we'll continue to see some sunny spells, and there'll be a range of temperatures, from the cooler north sea coast, to something closer towards the mid—teens in the warmer spots elsewhere. by then on thursday morning, could be quite a bit of cloud through wales, in much of england, although there's a hint of something sunnier towards southern england and south wales, although breezier as well. just may lift the temperature a little bit higher than it's been. a few sunny spells still around in scotland and northern ireland. that area of high pressure stays with us into the weekend. there is a chance on saturday, perhaps seeing a little patch of rain towards northern ireland and scotland. not set in stone. it is the exception to the otherwise largely dry theme. bye— bye. this is bbc news. the headlines: elon musk, the world's richest man, has bought twitter in a deal worth $41; billion. in a joint statement, the two sides said they wanted to make the social media platform better than ever and that the product would be enhanced with new features. russia's foreign minister, sergei lavrov, says there's a danger the war in ukraine could lead to a third world war. many in the east of the country are being forced to live underground, desperate for the war to end. five train stations were struck by russian missiles in western ukraine on monday. a turkish court has sentenced civil rights activist 0sman kavala to life in prison without parole on charges of attempting to overthrow the government. kavala was sentenced in connection with the 2013 anti—government protests in gezi park in istanbul. the 64—year—old has repeatedly denied the accusations.