parliament was forced into lockdown by a man initially described as a lone wolf terrorist. armed with just a knife and a rented car, 52—year—old muslim convert khalid masood killed five people and injured 50 before he was finally shot dead by the police. precisely what compelled masood to launch one of the uk's worst terrorist atrocities is still unknown — investigations by the security services are ongoing. but we have uncovered evidence that agents of the so—called islamic state were plotting a near—identical terrorist attack using secret messaging services. for over two years, our undercover journalists have been posing as fictional characters committed tojihad. via social media and secretive messaging sites, they have been in near constant communication with senior players in isis. injuly 2016, we discovered that the terrorist organisation was touting on twitter and facebook for british muslims to stage attacks at specific london locations. we began conversing with one of their recruiters, who then invited us to chat privately on a secret messaging site. the authorities were fully aware of our contact with the terrorist organisation. i managed to track down an is recruiter online. his name was "manager", and we always spoke on encrypted messaging services. i told him i was 17 years old and living with my parents. after a few weeks speaking to manager, it became clear that he was trying to groom me into doing an attack on uk soil. and one day he just started talking about targets. as the conversation developed the isis agent revealed an exact location he wanted to attack — westminster. he said it was a good target because it was crowded with disbelievers and civilians. and he said if i was successful with this operation it would be very damaging to the uk. later injuly 2016, a second isis agent outlined how such an attack could be carried out. he told me to just kill ordinary people — and that it wouldn't require a very complicated plan. the agent also directed our undercoverjournalist to a terrorist manual on the dark web. in gory detail it advises lone wolf jihadists on how to deploy a vehicle as a lethal weapon and how to target specific vulnerable parts of the body with a knife. the instructions relayed to our undercoverjournalist register like the blueprint to the westminster attack. masood used a car to mow down pedestrians on the bridge and a knife to fatally stab a policeman. could the same is operatives who were trying to groom our undercover reporter have also been inciting masood to violent action? well, it's inconceivable that khalid masood was not, in some way, either viewing or connected to other individuals who were viewing extremist material. you know, there is, arguably, no such thing as a lone actor or lone wolf as is often described. you know, these individuals are radicalised online, they have connectivity online, they use social media apps often in an encrypted fashion, and that is the methodology, if you like, the medium through which radicalisation occurs in the modern world. i thought maybe coming back would feel, maybe give a sense of closure. um, no. i think i'm kind reliving sort of the, um, the emotions. orlando was last here on london bridge on the evening of saturday june 3rd. just before 10 o'clock, as he and his friends were enjoying drinks, a white van appeared and shortly after, began running over pedestrians. in the distance you can make out a van and after that we started hearing a few screams. then down the road we see people running and there was a gentleman just across the street running and he kept on looking back and he kept screaming, "i have been stabbed, "i've been stabbed. " so i came up to the gentleman, there was another gentleman there and we got the man to lie on his front and we just started applying pressure to his back and calling an ambulance. the man was losing consciousness but as orlando desperately tried to keep him awake, he realised his own life was in danger. armed with a knife, the attacker was in close proximity and claiming more victims. he was very precise and i remember like he went into one man in particular who was furthest to the street and then ijust remember the woman in the red dress. she jumped on to him and she was doing her most to protect this person and then the group — it was like people started intervening. there was now like a police presence, a police presence. i remember like a bus was there and stuff and we got close enough until we heard the gun shots and then ijust thought to myself we don't know what is happening, who is shooting and we just, we ran. what i felt in the aftermath was a sense of guilt and yeah, like fear. eight people were killed in the attack and 48 suffered injuries — others like orlando have been inflicted with emotional scars that may never fade. on the night of the london bridge terror attack, many of us clung to our phones, checking for updates, hoping loved ones were safe. at the same time, members of is in syria were also busy on social media, celebrating and posting messages in honour of the attackers. our investigation reveals that is agents were busy plotting a similar attack in this exact location for over a year. in the summer of 2016, one year before the london bridge attack took place, our undercover reporter spent several weeks on an encrypted site in conversation with an isis handler. he repeatedly stated that london bridge was an iconic landmark they wanted to claim, a key target they wanted to hit. he was trying to persuade me to carry out the attack and he also gave me the option of doing it alone or along with a team. in december last year the same isis recruiter directed our undercover journalist to view some explicit terrorist tutorials on the dark web. one of them showed how to use a vehicle to kill people. the other showed how to use knives and home—made bombs for maximum impact on people. and finally there was a description of how to create a fake suicide vest — and how it can be used to stop the police from attacking you, if you are standing next to civilians. the recruiter's instructions bear all the hallmarks of the carnage that was eventually wreaked on london bridge. before they were killed by police, khuram butt, rachid redouane and youssef zaghba rammed a hired van into a crowd of people. they attacked others with knives. they wore fake suicide belts and had a stash of home—made bombs. do you think encrypted applications were used in the terrorist atrocities at the beginning of the year? there was definitely usage of encrypted communications between planners and terrorists and people that carried out some of those dreadful attacks. that i am afraid is common throughout every one of these incidents and there is also a role of watching videos online to either prepare themselves or train themselves. i think that they are both, i am afraid, current occurrences in these terrorist attacks. the police have yet to uncover any personal ties between thejune 3rd attackers and isis, but a pattern is emerging from our investigation, where the group's online directives are being mirrored in actual terror attacks. it's a pattern that is being reflected both here and abroad. one of the best examples was last year in the summer of 2016. both of the plots that happened in germany, both in wolfsburg and adler, both of these plots are now often described as perhaps some of the most prominent early plots in which you have evidence of direction, directly form isis in syria to people who were sitting in europe, basically telling them what to do, who to attack and how to attack. from its start, isis has realised the power of the web. its online recruiters worked hard to romanticise the idea that going to syria and taking up arms is a hijrah — a spiritual necessity. but recently the numbers of young muslim men and women making the crusade have dwindled. three, four years ago — simple, hop on a flight to turkey, go over what was essentially an unmanned border, walk straight in. now there's a system in place at the border, there's different controls at ports, at airports, they kind of know what they should be looking out for, some tell—tale signs of an individual looking to travel. so simply it's just far more difficult. lacking foot soldiers in syria, the terror group now has a new proclamation announced via twitter — if you cannot reach the caliphate, start waging war in your home country and what's more, we will help you. one of the first men to tweet this ominous sentiment was birmingham—born jihadist and supreme isis recruiter, junaid hussain. he developed something of a cult following on social media by weaving posts of his favourite music with sermons that glorified violent terrorism. in june 2015, our undercover reporter began a conversation with him. we exchanged some tweets then he suggested we talk privately on an encrypted messaging site. almost immediately, he asked me if i wanted to do something over here, in london. as i was leading him on i said, "yeah, but i needed guidance." and his response to that was that he could help and he could train me on how to make bombs from home. in further exchanges hussain described london as the heart of the crusader army and vowed to organise an attack. but his personal ambition to hit the capital was never realised. he stopped messaging us and we later discovered hussain had been killed by a us army drone. this wasn't an accident, and he wasn't eliminated for any physical acts of violence. what made hussain particularly dangerous to the american authorities was his ability to use social media as a lethal weapon, a recruiting and directing tool for wannabejihadists. yet his execution failed to extinguish the threat. hussain‘s legacy lives on. there are now hundreds of clone—like isis recruiters perpetuating the methods of radicalisation he helped pioneer. after hussain‘s death, another recruiter contacted us on twitter and directed us to a secret messaging site to continue the conversation. straight off, he told me that he had a test for me and this was all on basic knowledge of islam. and what made this difficult was, i was only given three seconds to answer each question. our reporter was also asked to provide photo id and pictures of his home. he spent weeks cross—referencing the information i had provided to see if it all matched and at the end of each stage he would refer me to another secret messaging site. and then eventually the operation he had planned for me was revealed. first off he wanted me to assassinate a police officer. he had devised a detailed plot including how to obtain firearms and bullets. in april this year, nine months after the recruiter mapped out his plan of attack, a parisian police officer was killed in an incident of marked similarity. isis claimed responsibility. the police are still investigating. the met police are aware of the so—called islamic state's online offensive against london but it is a tough task for them to sift out every genuine red alert. all the power and information is all with the terrorists and extremists who have at their disposal now encrypted apps that allow them to talk amongst each other around the world with very little coverage by the intelligence agencies whatsoever. this proliferation of terrorist activity on social media has forced the government to step up its anti—radicalisation campaign, prevent. but how much can it achieve when jihadists and their followers hide on the dark web and use encrypted messages to plot their attacks? we have been able to take down a quarter of a million pieces of data or videos and information that are in the online space that have been used to radicalise people. we try and effectively suffocate out messages from people like is and al-qaeda to make sure that they are not penetrating people's bedrooms and houses and turning normal people into terrorists and we have to keep investing in our people and intelligence services but also in working with industry to produce solutions that keep us just that step ahead of the bad guys. but the reality we might all have to accept is the danger posed by terrorists online is the new normal. i think the authorities have an unbelievably difficult task now. encrypted apps or anonymous web browsers or the dark net, these places online that are very, very difficult to properly monitor are proliferating very quickly. and one of the reasons they're proliferating quickly, is because they are actually valuable to everyone. they are very important channels forjournalists and there is no way for the authorities to crack down on these places without also potentially endangering ordinary people's privacy and the privacy ofjournalists and political activists with whom they agree. from this bleak perspective, isis are winning the war online. yet as authorities grapple with the problem, at a grassroots level, muslim communities in parts of london are using the web to fight back. hanif‘s charity — the active change foundation — is designed to stop vulnerable people from being preyed on by extremists. we know that there are other people out — out there that are reaching out to our communities, that are tapping into the human resource, that creates groups like al-anda, groups like isis, so we do exactly the same thing, we tap into the same human resource, we occupy the same space — online and offline — to change lives for the better. the active change foundation claims to have stopped hundreds of children from becoming radicalised and as a result has received help from an unexpected quarter — twitter. in the uk we've trained more than 500 charities on how to reach people using our platform and get the message out that says we are not going to be divided. the one thing that is important to remember is that when government technology companies and communities work together, and we each play our part, actually you can do a huge amount to keep the public safe, to challenge extremism and to make sure that those people who seek to do us harm are brought to justice and challenged, because although we can delete content on the internet we can't delete the ideology. threatened with more stringent regulation by government, tech companies like twitter are keen to promote their work in deprived communities. but could they be doing more to prevent terrorist plotting online? they do not want to take responsibility for the content that is shared on their site, because if they were legally responsible for everything shared on their site, they would have to check it before it was published — like a journalist or a newspaper does. given that there are billions of pieces of content being uploaded onto these platforms every single day, that is not possible. which means that they are in some ways stuck because, inevitably, their platform is going to be used by terrorists. one other thing, a lot of the big companies are now building in encryption into their services so they cannot decrypt it themselves. so when, for example, the government goes to whatsapp and says can you give us the messages between person y and person x, they can't even do it. i think they have to ask themselves some quite big moral questions that you know these guys are often the biggest proponents of surveillance than any government. they survey my details and your details every minute of the day and many of them sell these details to third parties to make profit and so they can't have it both ways and say you know, we are anti—surveillance, we are companies that don't believe in that, yet at the same time that is how they make their money. as our investigation was concluding, we received one final warning from the web. it was through a secret messaging site, where an is agent was trying to recruit me. he told me that i must be prepared to say goodbye to my loved ones and ready to carry out an attack soon. i think governments around the world have been slow to act on this problem. i would make exception to the british government which has led the way in terms of, you know, raising awareness of this issue. and we may have seen a surge and a blip, if you like, in attacks this year, i've got total confidence in the british intelligence agencies and police in thwarting and disrupting attacks in the future. that's all from inside out. don't forget the programme will be available on the iplayer — just head to bbc.co.uk/insideout. thanks very much for watching — see you again soon. you will have noticed we are in a speu you will have noticed we are in a spell of very changeable weather lasting all the way through much of next week. low—pressure meaning wet at times, windy, cool, but there are indications that from next weekend, things will turn a little more subtle, but it is far from set in stone. it is low—pressure that is across us stone. it is low—pressure that is across us at the moment, will be for the weekend and much of next week, and there is a cool wind blowing in through saturday, especially across the west and south, and plenty of showers from the word go through northern ireland and north—west england where it is pretty wet in the morning. showers developing more widely across england and wales as we go through the afternoon. at four o'clock, not too many showers in scotland, and those showers begin to fade away from northern ireland, so more of a try this stage. late in the afternoon going into the evening wales on the west will be seeing some sunshine, but more of central and eastern england on the south—east are seeing these showers at four o'clock in the afternoon. some places will miss them and stay dry, but they could be heavy and thundery. the showers will fade away gradually through saturday evening and saturday night, and it will be dry and clear for and saturday night, and it will be dry and clearfora and saturday night, and it will be dry and clearfor a time. it will be chilly going into sunday morning, down into single figures in some spots. then another area of low pressure coming in for the second pa rt pressure coming in for the second part of the weekend, and pushing south eastwards across england and wales, a fairly so slow process. and the wind picking up as well, especially sunday night into monday, gales and perhaps even a risk of severe gales as well, so we need to keep an eye on that and be aware of a spell of windy weather, monday remains blustery and a mix of sunshine and showers, although they may easily to in the day. from monday into tuesday, another possible weather system here, this one has a lot of uncertainty associated with it. southern parts of the uk could see a longer spell of the uk could see a longer spell of rain, and elsewhere showers will be most frequent through the north. low— pressure be most frequent through the north. low—pressure still very much on the scene, as we go into wednesday, so againa scene, as we go into wednesday, so again a source of showers on wednesday, longer spells of rain in places, still the risk of that across southern parts of the uk. the potential for some gales as well, and still on the cool side. but heading towards the end of the weekend into the weekend, this area of high pressure looks like becoming more established across the atlantic and edging towards us, and that is the source of potentially settling things down. it looks like from midmonth things will still be changeable, but the gaps between weather systems will be longer, so longer and more subtle spells, with warmer days, but under clear skies, chilly nights, so the potential for some mist and fog patches, potential frost. but nothing is set in stone because of this tropical weather activity in the atlantic, so there is the hint of something more settled on the horizon, but it yet may not happen. hurricane irma continues its deadly rampage across the caribbean. and now, there's another hurricane coming up behind it. in barbuda, where there's already overwhelming destruction, a mass evacuation is happening now to escape a second hit. everybody will tell you the same — they're not coping. everyone is in the same situation — and nobody can't help one another. amid criticism from mps, britain's relief effort is underway to the british overseas territories affected. irma is heading for florida, where those who can are leaving — others are hunkering down and hoping for the best. today is the day to do the right thing for yourfamily and get inland for safety. this storm is wider than our entire state. we'll be looking at the devastation wrought by the hurricane so far, and looking at whether there's worse to come. also tonight...