but questions are emerging about the vessel's safety. hello, i'm helena humphrey. we begin tonight in russia as security has tightened after authorities ordered the arrest of the leader of the wagner mercenary group. yevgeny prigozhin is a key figure in russia's full—scale invasion of ukraine. russia began a criminal investigation into prigozhin, accusing him of calling an armed rebellion. prigozhin accused russia of launching a deadly missile strike on wagner troops on friday, and called on russia's military to be stopped. tonight prigozhin claims that wagner troops have crossed russia's border with ukraine in multiple locations. he vows that he and his mercenaries will "destroy everything that's in our way." here is the wagner leader earlier. translation: they have been shooting at us, -

we've been shooting at them, and that has been going on these eight long years — from 2014 to 2022. sometimes the amount of shelling and exchange of fire has increased and sometimes it has eased. on 2a february there was nothing extraordinary. now the russian defence ministry is trying to deceive the president and the public by claiming there was insane aggression on the part of ukraine and they were going to attack us, along with the entire nato bloc. so the so—called "special military operation" on 2a february was launched for completely different reasons. the bbc is unable to verify prigozhin�*s claims and images of wagnerforces in russia. moscow is tightening its security in response to developments — here's footage of military tanks in russia's capital. also officials in two regions bordering ukraine are urging citizens to stay indoors or not to travel south.

and the government of voronezh has urged people to avoid the m4 motorway connecting moscow to southern regions of russia, because a military convoy is moving along it. the kremlin has said: internationally, the white house is also reacting, releasing a statement saying they are monitoring the situation. meanwhile, the deputy commander of the russian ukraine campaign, sergei surovikin, told wagner soldiers to stand down. translation: i addressed the command, officers - and fighters of wagner pmc. together we've been down a long and difficult road. we fought with you, we risked it, we suffered losses, we had victories together, we are of the same blood. you must do this before it is too late. obey the will and command of the elected president of the russian federation. stop the convoys, return to bases and places where you are stationed.

live now to ambassador bill taylor, former us ambassador to ukraine. welcome to the programme, thank you forjoining us. firstly, your thoughts on what we are seeing unfolding in russia this evening? so this is serious for putin. there are reports, more recent reports, all reports earlier going to be suspect— but there are some reports coming in that says some of the ministry of defence forces are now abandoning their leaders and going over to the prigozhin forces. so again, we don't have this family at, but there is an indication that there is momentum behind prigozhin and his wagner group, as they move north. and has you havejust reported, the military and police and security services in moscow are taking this

extremely seriously, closing down roadways, putting armoured vehicles in downtown moscow, all to say that this is serious. the russians are taking this very seriously, it sounds like they should. they do appear— sounds like they should. they do appear to _ sounds like they should. they do appear to be _ sounds like they should. they do appear to be taking - sounds like they should. they do appear to be taking it - do appear to be taking it seriously, in fact though kremlin has accused prigozhin of trying to mount a coup. do you give out any credence? i do, i do. this is almost certainly an attempted coup. he has denied it, he says no, it's not a coup, it is a march for justice. that sounds like a coup. he is clearly moving in the direction of moscow with forces, he says he has 25,000, but there are reports of other wagner units that are stationed up wagner units that are stationed up and down that road going towards moscow. so this is all the possibilities, all the indications that this is serious on prigozhin�*s part, and it could well be a coup. and do you think he could

succeed? it and do you think he could succeed?— and do you think he could succeed? ., , , . succeed? it would be difficult. priuozhin succeed? it would be difficult. prigozhin doesn't _ succeed? it would be difficult. prigozhin doesn't have - succeed? it would be difficult. prigozhin doesn't have the - prigozhin doesn't have the forces, doesn't have the strength, doesn't have the aircraft for example, all the military equipment that the russian ministry of defence does. but as we are now hearing, some of the soldiers in the ministry of defence forces are defecting to prigozhin. so he has got momentum — the question is the loyalty of those soldiers, the loyalty of those soldiers, the loyalty of those soldiers, the loyalty of the officers, the loyalty of the officers, the loyalty of the fsb, the security services. when putin can no longer command the loyalty of these services, he is in trouble.— is in trouble. and on that oint, is in trouble. and on that point. what _ is in trouble. and on that point, what do _ is in trouble. and on that point, what do you - is in trouble. and on that point, what do you think| is in trouble. and on that. point, what do you think this says about putin's grip on power? it says about putin's grip on ower? , , , ., ~' says about putin's grip on ower? , , , ., ~ 2 power? it is being shaken, it's bein: power? it is being shaken, it's being tested. _ power? it is being shaken, it's being tested. again, - power? it is being shaken, it's being tested. again, his - being tested. again, his forces, the ministry of defence forces, the ministry of defence forces, have the equipment,

have the aircraft, have the tanks. they have the military equipment to, in numbers, put down prigozhin�*s forces. prigozhin�*s forces are mainly infantry. they have some equipment, some armoured vehicles, they apparently have some artillery as we have heard over the last couple of weeks. prigozhin has complained that the ministry of defence is not giving him enough ammunition for his artillery. so we know he has some heavy equipment. the question really comes down to the loyalty of those other units that putin hopes will defend him and stay loyal to him, but putin has got to worry that there are a lot of soldiers who have been killed, and that means there are a lot of russian families who have had brothers and fathers and sons killed, and they may be more sympathetic to prigozhin. so how do you think then, in light of what you have just said, how do you think putin will respond?— said, how do you think putin will respond? undoubtedly he will respond? undoubtedly he will be pushing _

will respond? undoubtedly he will be pushing his _ will respond? undoubtedly he will be pushing his units, - will respond? undoubtedly he will be pushing his units, hisi will be pushing his units, his ministry of defence, his fsb forces, his security forces, to crackdown ruthlessly, heavily on prigozhin. it could be a real battle. prigozhin is hard to understand, but he seems to be determined, he seems to be convinced that he can move on moscow. so if that is a clash, it could be bloody, it could be a real battle among russians. the interesting thing is what this means for the ukrainians. the ukrainians, as you have been reporting, amounting this counteroffensive, and the counteroffensive, and the counteroffensive is right now building up steam, it is gaining momentum, it has the potential to break through russian lines. and if the russians are now worried about their chain of command, and what is going on in moscow, and rostov—on—don, then the

russians that are supposed to be fighting ukrainians may be distracted and may even... may even run. so this could be greatly to the advantage of the ukrainians. i greatly to the advantage of the ukrainians.— greatly to the advantage of the ukrainians. i wanted to ask you about that- _ ukrainians. i wanted to ask you about that. i— ukrainians. i wanted to ask you about that. i know _ ukrainians. i wanted to ask you about that. i know you - ukrainians. i wanted to ask you about that. i know you were . about that. i know you were recently in ukraine, and do you think we could potentially see — and i stress potentially— an endgame that does not involve ukrainians having to defeat russians on the battlefield? instead, where putin is not from within?— from within? it's possible, it's certainly _ from within? it's possible, it's certainly possible. - from within? it's possible, it's certainly possible. we | it's certainly possible. we can't count on it, the ukrainians don't count on it, they are continuing to fight and will continue to fight. but many people, analysts and observers all along have said that this fight will only go on as long as president putin wants it to. if he is in trouble, if he is threatened, if he is removed in a coup that might happen then it could well

be that this could be the end of the russian invasion of ukraine. of the russian invasion of ukraine-— of the russian invasion of ukraine. ~ ., ., ~' ukraine. what do you think ultimately _ ukraine. what do you think ultimately this _ ukraine. what do you think ultimately this says - ukraine. what do you think ultimately this says about i ukraine. what do you think l ultimately this says about his grip on power? his ultimately this says about his grip on power?— grip on power? his grip on ower grip on power? his grip on power is — grip on power? his grip on power is being _ grip on power? his grip on power is being tested. - grip on power? his grip on power is being tested. it l grip on power? his grip on | power is being tested. it is being tested. he, however, has clamped down so heavily, clamped down so heavily, clamped down so heavily, clamped down so heavily on all aspects of russian society — the military, the police, the local level — he has, up until now, had real control. however we have seen that dictators can stay in power until they don't. until they crack, until they, like we said earlier, until they lose the loyalty of those around him. and prigozhin has been one of the people around him, and if prigozhin is now fighting against the ministry of defence, is trying to —— thatis of defence, is trying to —— that is trying to defend putin, then president putin is having a hard time holding on to

power. a hard time holding on to ower, �* , ., a hard time holding on to ower. ~ , ., . ., power. ambassador william ta lor, power. ambassador william taylor, former _ power. ambassador william taylor, former us _ power. ambassador william i taylor, former us ambassador power. ambassador william - taylor, former us ambassador to ukraine, really great to get your thoughts here on bbc news, thank you so much.— here in the united states, intelligence agencies have declassified their report on the potential links between the origin of covid—i9 and the wuhan institute of virology. the report says us intelligence found no direct evidence that the covid—i9 pandemic stemmed from an incident at the wuhan institute. i spoke with our correspondent peter bowes for more on this story. thank you so much for being with us. what more does this report tell us, peter? this report is quite narrow in its scope, it's only four pages long, but the key headline which frankly doesn't really take us much further forward, it doesn't give us much new information — but it is that conclusion that there is no direct evidence that a research—related incident at the wuhan institute led to the covid pandemic,

which some people suspected it came directly from that particular research lab and it is a place that we know had been doing research into the coronavirus before the pandemic. we know that some genetic engineering work had been going on there, and some workers at laboratory fell sick. nevertheless, no direct evidence that anything that was happening, any research programme, led to the global pandemic. but i say that this report is quite narrow in its scope because what it doesn't do is explore in any detail at all, the two most broadly plausible reasons for the spread of the pandemic — a, that it could have been spread naturally, perhaps from an infected animal, or indeed it did come from another laboratory, possibly in china, which of course is something that beijing denies. and peter, are all intelligence agencies on the same page in terms of how the pandemic began? no, they're not, and we've known for some time

that the different agencies in this country have some degree of disagreement. yes, some agencies agree that it could well have been a natural spread of the virus, but others like the department of energy and the fbi veer more towards the argument that it could have originated from a laboratory though it's got to be said, the department of energy in their report was released with a low level of confidence so far from conclusive. what there is agreement, it seems, across agencies, is that this virus was not genetically created, it wasn't genetically engineered. and how long—awaited was this declassification? it's been waiting for us for some time. there's been clamouring in many areas for release of more information. there was a law passed in congress earlier this year, president biden signed it and this release in the last few hours is a result of that. many people see this

as crucially important. from a scientific respective to absolutely try to get to the bottom of the origins of covid—i9, acknowledging that it may well be only a matter of time before there is another virus that spreads around the world and everything that can be learned from the last one in terms of stopping that spread or indeed preventing it, must be aspired to, everything must be done that is possible to get to the root of the cause and clearly that hasn't been done yet. 0ur correspondent there, peter bowes. peter, thanks a lot. the us supreme court on friday handed the biden administration a major victory on a key immigration case, ruling that republican—led states do not have the legal right to challenge a policy concerning federal immigration enforcement. the justices, in a rare 8—1 ruling, cleared the way for the biden administration to reinstate rules prioritising the deportation of immigrants based on serious criminal records, national security threats, and migrants who recently entered the us. writing for the court,

justice brett kavanaugh rebuked these claims, writing: we turn now to warnings over the safety of the titan sub that imploded near the wreck of the titanic this week. according to emails seen by the bbc, the boss of the company that operated the trip repeatedly dismissed concerns over the craft�*s safety. deep—sea specialist rob mccallum told 0ceangate ceo stockton rush that clients could be at risk. and he urged him to stop using the sub until it had been classified by an independent body. in an email sent in 2018, maccallum warned rush that:

stockton rush replied: earlier, my colleague, sumi somaskanda, spoke to our correspondent, carl nasman, who is on the scene in boston. carl, it's great to see you. first of all, the us and canada have announced that they are launching investigations into what happened. tell us more about what they are going to be examining. yeah, earlier, of course, we heard from relatives of one of the people that was on that vessel, hamish harding. they have been calling for a full investigation into this incident. it looks like they will be getting two. 0n the us aside, hearing today confirming to bbc news that the us national

transportation safety board will be involved in an investigation into this incident which will be led, we believe, by the us coast guard. and on the canadian side, their transportation board will be looking into this incident as well. they have announced they are launching a probe and they will also be conducting some interviews on the ground in newfoundland, and stjohn�*s — which is where all of the ships had been launched as the closest landmass to where the dive site is — so we are expecting some investigations now. we're not sure exactly when they will ramp up or how they will be coordinating between each other, but there are now some national bodies looking into this. and, carl, this announcement coming as we mentioned, there are more questions being asked about safety standards at 0ceangate. what have you been hearing? yes, there has been a chorus of concerns now emerging, many of them as we heard in that e—mail exchange coming from 2018, so a testy exchange, several e—mails we have seen

at the bbc between the two, rob mccallum, an expert in the field, and the ceo himself, the late stockton rush. and this was more of the same. we have heard this from several experts — concerns about the materials that are used — were used in the titan, in that hull, the carbon fibre used, outside of the norm for the industry. we also heard concerns about the lack of certification of the titan, and even saying that it should stop use altogether until there was a certification done. now, interestingly, this was back in 2018. the first dive to the site of the titanic wreckage was actually in 2021, so this was several years before the titan started making these trips. and also, more recent concerns being raised in just the last few days — the director of the movie titanicjames cameron, who's also made several — more than 30 trips to the titanic wreckage himself. he's been speaking out about similar concerns. so, this has a timeline dating all the way back five years or so, even before the titan was fully operational in terms of going to those depths.

and, carl, can you bring us up to date on recovery efforts to pick up the debris of the titan submersible? these recovery efforts are continuing and they're being led by some of these rovs — or remotely operated vehicles. there is at least one in the area that will continue to scour the ocean floor some 2.5 miles below the surface. looking at the debris itself, we know that five key pieces of the titan have been detected already. they'll take a closer looks, maybe send some images back above, and eventually try to recover those items altogether, bring them up to the surface and look at them closely, examine especially any bits of carbon fibre they can find, to see if that material had been stressed orfatigued, if maybe that had led to this catastrophic implosion. they'll also, interestingly, be looking at these debris fields — there's a couple of them that they found — they can tell by the size and shape, approximately at what point that vessel might have imploded.

a wider field would indicate that it imploded earlier into its dive. a much smallerfield would imply that it made it nearly to the bottom before some sort of catastrophe took place. well, in the last hour, i spoke with parks stephenson, the executive director at uss kidd veterans museum. he's an explorer and expert in deep—sea exploration. parks, thank you so much for joining us on the programme. i want to get your thoughts, your reaction to this tragedy. of course, i am overwhelmed by the human loss here in this tragedy. ph nargeolet was a colleague of mine, i've been on expeditions with him and his loss is very keenly felt, so that's the overriding emotion is the human loss in this tragedy. we are very sorry to hear about the loss of somebody who was one of your colleagues.

now, i understand that you were approached by 0ceangate a number of years ago during the construction of this sub, the titan. you didn't take that position. tell us more about that decision. yes, i was an aerospace engineer at the time and i did deep ocean exploring, largely concerned around titanic at the time. 0ceangate had approached me with an offer for employment to be an onboard titanic expert. at that time, the submersible titan was being constructed and i got a look at some of the conceptual drawings of the vessel, and i had some concerns on a very basic level. granted, this is my opinion. i was not directly involved in the construction or the selection of materials used in the submersible, but what i saw in these drawings ran counter

to everything in both my engineering and my diving experience. how so, specifically? can you give an example? you mentioned there, for example, materials? well, yes, from a very basic level, when you are down in the extreme deep, pressure is your greatest enemy and it's going to be pressing in on all areas of the container that you're in. air is incompressible and the outside pressure is trying to press in on that container and release that air, so, therefore, in my opinion, the ideal shape for a pressure vessel should be spherical in shape. it should be made of the strongest metal available, titanium. and all of the fittings that attach the halves of the sphere should be of the same material, should be homogeneous. this design was cylindrical in shape. there was a cylindrical body with two end caps. the materials used

were not homogeneous. you would have titanium end caps glued to a carbon—fibre body. now, just in my opinion, that was a very basic flaw. i do understand that they were trying to be cutting edge on it, but it seems to be violating some of the basic tenants of physics of operating in the deep — to my mind. 0k, well, i want to play you what the co—founder of 0ceangate, guillermo soehnlein, had to say, and then i want to get your thoughts. let's listen to what he had to say first. any expert who weighs in on this, including mr cameron, will also admit that they were not there for the design of the sub, for the engineering of the sub, the building of the sub and certainly not for the rigorous test programme that the sub went though. parks, were you satisfied with the test programme that this sub went through? well, as guillermo said in his

recording, i wasn't there. i was diving in other submersibles at the time that 0ceangate were deploying the sub during the time of their testing. i received word — second hand, admittedly — that titan was not passing her certification trials and that she never obtained a proper certification. so, guillermo is correct. i was not there. i was not there to oversee it. but there are certain standards that every other submersible in the community followed and, to my knowledge, titan was the only vessel that failed to follow those standards. crosstalk. what i can say from that is why are we talking today? well, as you say, very sadly,

we are having this conversation and just to go back to that moment when you declined to take a position up at 0ceangate. i wonder, did you communicate your concerns to the company and what was their response to what you had to say? i was contacted by who i assume was not one of the top—level individuals. this certainly was not stockton rush himself, it was one of the members of his staff, and i just said that this design does not go with... ..it does not make me feel comfortable and i regretfully declined to accept their invitation. that was the extent of it. they accepted that and i never heard from them again. we want to bring you our top story again. russian authorites have ordered the arrest of the leader of the wagner mercenary group, yevgeny prigozhin, with claims that he and his men have crossed the borderfrom ukraine into russia and will "destroy anyone who stands

in their way." so far, there's no evidence of their advance. this comes shortly after russia began a criminal investigation into prigozhin, accusing him of calling for an armed rebellion. according to russian media, a plan known as 0peration fortress has been activated in the city of rostov—on—don, which lies about 100km east of the ukrainian border. essentially, it is a plan for personnel to be in "full readiness. we will continue to monitor this. thank you for your company. i will see you soon. good night. hello. after what's been another fairly warm week for many of us, the weekend is set to bring something even warmer. in fact, i think the days at times will feel quite hot and the nights will be very warm and humid as well. but as we head into sunday,

we are going to see a bit of a change. some thundery downpours swinging in from the west courtesy of a frontal system, which is a long way away to the west of us right now. for the short term, high pressure isjust about in charge and around this area of high pressure, particularly as these weather fronts squeeze in, we've got a feed of humid air wafting its way across our shores. so, quite a warm and humid start to saturday morning with a fair amount of cloud actually, and some mist and murk around some of the coasts and over some of the hills. a lot of the cloud will tend to break through the day to give some spells of sunshine. a bit of rain moving across the far northwest of scotland. there's a small chance for the odd shower in parts of northern england, down into the midlands, but wales and the south of england likely to see the lion's share of the sunshine and wherever you are, it is going to be a warm day. 2a degrees for belfast, 25 for aberdeen, 29 the expected high in london. and that warmth does not ebb away quickly as we head into the evening. in fact, temperatures holding up at around 23 degrees in london and in sheffield

at 10:00 in the evening, so it could well be a little bit uncomfortable for sleeping. those temperatures falling a little bit further into the early hours of sunday. but with the humid air in place, sunday is going to turn into another very warm day. however, this frontal system pushing in from the west will bring a change for some of us with a band of heavy, thundery rain already in place across northern ireland first thing. that will push its way eastwards and ahead of it, some showers will pop up across parts of northern england, eastern scotland. these could be heavy and thundery in nature. but further south and particularly further southeast, it should stay largely dry with lots of sunshine and that warmth being squashed into the southeast corner. so, temperatures in london likely to get to 31 degrees, but just 19 for belfast. fresher in the west. and that fresher air will move across all parts of the country as we move into the start of the new week. there are, though, further frontal systems lying in wait, so we will see further outbreaks of rain at times and potentially some quite strong winds as well, particularly towards the north and the west of the uk. not as much rain further south

and it is not going to be as warm as it has been.

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