Saving the Great Barrier reef from destruction we have a special report on the fight to protect one of the worlds natural wonders. Hello and welcome to bbc news. There have been fierce clashes between turkish troops and Kurdish Forces in northeastern syria. Since hostilities began on wednesday, nearly 50 civilians are thought to have died on both sides of the frontier, and more than a hundred thousand people have fled their homes. Much of the latest fighting has been in the border area near ras al ain. The Turkish Military have entered the strategically important town, but theyre facing stiff resistance from the kurdish led, Syrian Democratic forces. Our correspondent orla guerin is on the turkish side of the border. Her report contains flashing images. The front line in a conflict that is spreading fast. Turning Northern Syria into a battleground. Alarming washington and europe. The smoke is rising from the key town of ras al ain. And inside the town, this pro turkish fighter says weve just arrived. And give thanks to god. Then ducks to avoid incoming fire. But Kurdish Forces cant offer much resistance. Ras al ain has all but fallen and other towns are expected to follow. The turks and their allies are stamping their authority here. And syrian Kurdish Forces are looking very much alone, urging the us allies to keep their side of the bargain after the kurds died in their thousands fighting islamic state. Translation our allies guaranteed us protection but they abandoned us without warning and decided unjustly to withdraw their troops from the turkish border. We call on our allies to fulfil their moral obligations. Us forces arent far away but theyre holding fire as the kurds take heavy casualties. This footage, filmed exclusively for the bbc, shows american troops standing by at the edge of turkeys planned safe zone. Even leading republicans accusing President Trump of a shameful betrayal. And turkeys offensive is inflicting an agonising human cost. This motherfled ras al ain, carrying her sick daughter. She says the girl has had no food for the past four days and is barely alive. What is this . She cries. Erdogan, look at this. And in the kurdish stronghold of qamishli, mass funerals today forfour dead. Two fighters and two civilians. Syrias kurds say they have given their blood to fight is for the world. But there is no help for them in their hour of need. Orla guerrin there. Lets get some of the days other news the wife of an american diplomat who left the uk, despite being a suspect in a fatal crash, has been left devastated by the incident, says her lawyer. 19 year old harry dunn died when his motorbike crashed into a car being driven from a Us Military Base in england. The suspect, 42 year old anne sacoolas, also said that she would like to meet the victims parents. Negotiators from the uk and eu are holding whats being described as intense technical discussions on getting a new brexit deal. About a dozen british officials, including lead adviser david frost, are taking part in the brussels talks. The meetings are expected to continue throughout the weekend, with the next 48 hours being seen as crucial. At least one person has died in a fast moving wildfire, north of los angeles. The fire is being fuelled by gusty winds, warm temperatures and low humidity. Around 25,000 households have been forced to evacuate, while hundreds of thousands have had their electricity cut to guard against sparks from power lines setting off more fires. Thousands of people have marched through the streets of hong kong to protest against an emergency law banning the wearing of masks. The government brought in the ban in an effort to deter pro democracy protesters. Many protests in recent weeks have descended into violence, but saturdays demonstration was largely peaceful. Typhoon hagibis has hitjapaan with record breaking amounts of rain and powerful winds. At least two people have been killed and millions of people had been advised to leave their homes. From tokyo, Rupert Wingfield hayes reports. This is the hii river, near mount fuji. Usually it is a Clear Mountain stream. Today, it was turned into a raging, boiling torrent. Across central japan, typhoon hagibis has dumped record amounts of rain. 0n the Southern Side of tokyo, the tama river is now close to bursting point. Tens of thousands of people who live along its banks have been ordered to leave their homes. The big dangerfrom these sorts of events is water. Water is the thing that can do real damage, both if this river burst its banks, if it causes landslides in the mountains or, of course, when it reaches the sea. As night fell over tokyo, the eye of the storm approached, bringing winds gusting to over 140 kilometres per hour. This is the centre of shibuya, one of the busiest places normally in tokyo on a saturday night. I dont think i have ever seen it as deserted as it is tonight. In fact, the whole of tokyo is incredibly deserted. The centre of the storm has now passed to the north of the city and it does not appear to have brought the really destructive winds that were first feared. That is good news for everybody including, of course, rugby fans. Today, japans rugby team had to wade their way onto a sodden field for some last minute practice. Saturdays big match between england and france had to be cancelled. But there is hope that japan will be able to take on scotland on sunday in a match that will decide which team goes through to the knockout stage of the rugby world cup. Rupert wingfield hayes, bbc news, in tokyo. The president of ecuador has ordered military control of its capital, quito, in an attempt to end days of violent clashes between Security Forces and indigenous protestors. Asign a sign that the state appears to be losing control, protesters occupy the roof of a government building. The violence appears to be worsening. More than a week after it began. The police response, teargas and hoses, while protesters build barricades and set fire to tyres. The demonstrators are demanding the government wrap austerity measures. Fuel more than doubled since subsidies were removed. Since the protest began last week, hundreds of people have been arrested and at least one protester has died. Reacting to these chaotic scenes, president lenin moreno has placed the capital under strict curfew and military control, insisting he would restore order in all of ecuador. Indigenous leaders have accepted to hold direct talks with the president , the first sign of a potential breakthrough. But for now, the country seems far from having order restored. At least one person has died and another 18 have been injured in a new orleans building collapse. The authorities have cleared the area around the site, amid fears of a further collapse. Shaun hassett has more. Get to the back. This is the moment when the upper floors of the building gave way. Still under construction, it was said to be a new hard rock hotel, now it is a disaster side. There were lots of noise. We saw workers up there. It was crazy. I cannot even imagine what it was like up there. We thought it was gunfire but it wasnt, it was a building collapsing. Construction workers run for their lives, some escaped injury bya for their lives, some escaped injury by a matter of metres. This man was on the 18th floor at the time. By a matter of metres. This man was on the 18th floor at the timelj by a matter of metres. This man was on the 18th floor at the time. I saw one guy kind of fall. Things. Smoke started coming from everywhere so smoke started coming from everywhere soi smoke started coming from everywhere so i could not really see where the problem started. Emergency crews we re problem started. Emergency crews were on the scene quickly, rescuing people from the rubble than clearing the area around the building. A second part of the building fell off about an hour after the initial collapse. Authorities say the remaining part of the building is structurally u nsta ble remaining part of the building is structurally unstable and a further colla pse structurally unstable and a further collapse as possible. They are also worried craig could come crashing down. Obviously, this is very serious. A crane. Down. Obviously, this is very serious. A crane. Some down. Obviously, this is very serious. A crane. Some of the building that has collapsed is placing a load on the crane away from the collapsed side. It is not clear at this stage what triggered the collapse. Stay with us on bbc news. Still to come are you a slow walker in your 40s . We may have some bad news for you. Parts of San Francisco least affected by the earthquake are returning to life, but in the marina area where most of the damage was done, they are more conscious than ever of how much has been destroyed. In the 19 years since he was last here, he has gone from being a little known revolutionary to an experienced and successful diplomatic operator. It was a 20 pound bomb which exploded on the fifth floor of the grand hotel, ripping a hole in the front of the building. This government will not weaken, democracy will prevail. It fills me with humility and gratitude to know that i have been chosen as the recipient of this foremost of earthly honours. This catholic nation held its breath for the men they called the 33. And then, bells tolled nationwide to announce the first rescue and chile let out an almighty roar. This is bbc news. The latest headlines heavy fighting continues as Turkey Presses ahead with its military operation against kurdish fighters in northeast syria. Torrential rain and tornado like winds have lashed japan in the countrys worst storm for 60 years. The kenyan athlete, eluid kipchoge, has said he hopes that breaking the two hour mark for the marathon will inspire people to think that anything is possible. He ran the distance in one hour 59 minutes and a0 seconds at a special event in austria. It wont be recognised as a world record, because it wasnt an open competition, and he had numerous pacemakers helping him. Ade adedoyin reports. Eliud kipchoge came to vienna with his sights set on one thing. Running the quickest marathon ever. And from the word go, he was on track and well ahead of pace. The Detailed Planning was paying off. Some 41 pacemakers have been employed by the organisers to be part of this challenge and every time they go past this point near the finishing line, they rotate. Just one of the many steps that have been taken by the organisers to ensure that kipchoge ducks under that two hour mark. Special shoes propelled the kenyan further forward with each pace. They calculated the optimum course and weather, taking into account his biorhythms and even projected a laser onto the road. But all this means it cant be ratified as a world record by athletics world governing body. Hes pointing. Come on, he says. As the finish line approached, the pacemakers stepped away and kipchoge strode into history. Into the final 20 seconds, eliud kipchoge. Looks over his shoulder. 1 59 a0 the unofficial time. Im the happiest man to run under two hours. In order to inspire many people. To tell people that no human is limited. You can do it. I expect more of that, for all of the world to run under two hours. Already a great athlete with world and olympic titles, kipchoge will now be remembered forever. Ade adedoyin, bbc news, vienna. How many of us really know what were agreeing to when we click to accept the terms and conditions as we access websites and apps . 0ften, were handing over valuable personal data for free, and, as our media editor, amol rajan explains, its a commodity thats increasing in value. Very, very few of us give any thought to what were signing up to when we give away our personal data online. All around us are machines whose very raison detre is to know us better than we know ourselves. Alexa. Whats the weather in london today . In london its 19 celsius with clear skies and sun. Com pa nies a re co nsta ntly developing their profiles of us. Thank you. This is an example from amazon of what is collected and analysed. Content you viewed or searched for. The apps that we look at are part of an attention economy. In return for often free services, you donate attention and data. This is what you signed up for with facebook. We receive information about your online and offline actions and purchases from Third Party Data providers. That said, its the World Wide Web which specialises in turning your personal information into a commodity. With starbucks, the Website Activity is linked to your social networks to allow them to track the activities of their members. All around us, invisible but forever accumulating, is an almost unimaginable amount of data. Every time we look at our phones or make an electronic transaction, were adding to it. And while you or i may not give this much thought, the most powerful companies in Human History certainly do. For them, your data is gold dust. This lawyer, who successfully brought a case against cambridge analytica, says it is about power as much as privacy. If the product is free, where is the cost . I think to most of these companies, you, the user, are not the customer. The customer is normally an advertiser that takes your personal information. Its about you having a say and some control over how that information gets used. Surveillance capitalists take your private human experience, they turn it into behavioural data, they package it as predictions of what you will do now, soon and later, and they sell that to business customers who have a very serious commercial interest in knowing about what youre going to do in the future. In a world in which data is the most powerful commodity, the question of who owns and controls our data needs to be given much deeper thought. At the moment, a few mostly californian companies are setting the terms of the debate. Amol rajan, bbc news. A team of International Scientists has discovered a surprising link between the speed of our walking, and how fast our brains and bodies are ageing. In a study of 1,000 people in their 40s in new zealand, researchers found that not only were slower walkers bodies ageing more quickly their faces looked older and they had smaller brains. We measured it in three ways. In this study where all the data is coming from. We measured the average speed at which people are walking, the normal pace. And we measured the maximum speed without running and we measured a dual task gait speed, meaning people had to recite alternating letters of the alphabet while walking. And each of these three measures are equally associated with accelerating ageing measures we have been investigating. Theres going to be a big variation in individuals but these studies show that on average if you tend to walk slower, as you get older, this is associated with a decline in function. And there is a big link iiow function. And there is a big link now established with how our brain works and how we walk. So walking is a very complex process. It involves not only good function of the muscles and the bones and the joints, but also, it is also dependent on proper functioning of the brain. Indias Prime MinisterNarendra Modi has called for a new era in relations with china, following his summit with xi jinping. The leaders of the worlds two most populous nations held one to one talks at a resort near chennai, in the south of india. Neither side mentioned kashmir the disputed region controlled separately by india and pakistan and where china is seen as an ally of islamabad. President xi described the summit as a candid discussion between friends. Polands populist government is being put to the test on sunday, as voters go to the polls for a general election. The right wing law and Justice Party which came to power in 2015 face a challenge from the centrist Civic Coalition alliance and left of centre lewica. The far right party, confederation, is hoping to Enter Parliament for the first time. Australias vast Great Barrier reef is justifiably known as one of the seven wonders of the natural world, and yet until the mid 1970s it was constantly under threat from government plans for mining and oil exploration. Eddie hegerl has spent his life campaigning to stop the reefs destruction. Hes been speaking to our witness history team. The barrier reef has a wonderful array of fish. But really the things to me that are the most spectacular ones they know the least about, and thats the enormous variety of marine invertebrates. Its an enormous number of species. Its pretty ha rd not enormous number of species. Its pretty hard not to have a day where you dont see something that you havent seen before. In mid 1967, there was an application to mine on ellison reef. The man who wanted to mine itfor ellison reef. The man who wanted to mine it for limestone actually called it a dead reef. Eye and a group of colleagues who had been studying coral reefs and fish were actually asked to go and carry out a Scientific Survey of the reef to determine if what he said was true. We spent five days diving and found it to be a perfectly normal reef which certainly should not be allowed to be mined. The Queensland Government of the days attitude was that the reef was a nice pile of limestone that could be carted away to Southeast Asia and made into cement. The queensland premier, joh bjelke petersen, thought that mining on the Great Barrier reef would create lots of employment. He com pletely create lots of employment. He completely misjudged the queensland public. They had to start, obviously, working full time just as a barrier reef campaigner. The volume of mail, requests for information, and media interviews was just endless. The final decision of the mining application came about seven months later. It was only saying there would be no mining at alison reef. The really big shock came on the 24th of december 1968. The thought of having an oil industry throughout the reef region, potentially, was just appalling. Ive thought this was going to be a lot harderfight, ive thought this was going to be a lo