than it should have been, unacceptably high, and not enough was done to mitigate against that. from the summer of 2016, lucy letby was moved to administrative duties. but there was still no formal investigation into why so many babies had died or come close to death. the internal documents we've obtained reveal one consultant asked for the police to be called in. a hospital manager replied: "action is being taken," and ordered: "all emails cease forthwith." but the police weren't called. we had a number of meetings with senior management. it was quite clear that, they weren't going to budge and,

they didn't think it appropriate to go the police at that stage. instead, the hospital asked the royal college of paediatrics and child health to look at what had been going on in the unit. in november, the college called for the hospital to conduct a thorough external, independent review of each unexpected neonatal death. but the deaths weren't investigated fully. was this a cover up? i don't know how you'd define a cover up but to us the... the evidence in front of us was quite clear — it felt that they were trying to engineer some sort of narrative or way out of this that didn't involve going to the police. and if you want to call that a cover up then, that's a cover up. there were deaths and near deaths,

which could not be explained, and were unexpected. and thatjust does not happen on a neonatal unit. but unfortunately, there was a concern about how it would look. so the reputation of the organisation and protecting that reputation was a big factor in how people responded to the concerns raised. hospital managers went out of their way to protect lucy letby. we've discovered they upheld a grievance she'd brought against the consultants for getting her removed from the unit. tony chambers concluded the meeting, with the statement to us, saying that we were to apologise to lucy letby, and that a line had been drawn,

and that we were not to cross that line and, if we were to cross the line, there would be consequences. this document hasn't been made public before, either. it's a written apology the consultants were forced to send to lucy letby. it says: "we would like to apologise for any inappropriate comments. we are very sorry for the stress and upset that you have experienced in the last year." two consultants were even ordered to attend mediation sessions to make the peace with lucy letby. the doctors didn't back down. two months after the apology, the hospital asked the police to investigate. but only after the consultants pushed them.

to their huge credit, they made the collective decision that they would stay and see this through, and i am full of admiration for that courage. so, even afterthe meeting, when they were told that we'll draw a line under this or there'll be consequences, they still persisted in saying, yes, but we still have questions that haven't been answered. and we still feel that the police are the right people to discuss this with. do you think it's the case that if you hadn't persisted, - there would never have been a police investigation? - i'm sure, yeah, that was the intention of the executives, was to somehow close this case. tony chambers later resigned as chief executive. he told us what he said to the consultants had been

taken out of context. and that prompt action was taken after he was first told of serious concerns injune 2016, including reviews of deaths. he said all his "thoughts are with the children at the heart of this case" and their families. he's "truly sorry for what all the families have gone through" and that he would "co—operate fully. . .with any post—trial inquiry". three weeks after being told about the baby deaths, cheshire police launched an investigation in may 2017 — operation hummingbird. it's really hard to believe that anybody would be harming tiny babies, and that was the general feeling at that point, and it wasn't until we got further on in the investigation,

where we'd established that a crime had occurred, that really, the size of this investigation and what we were about to embark on really kind of hit home for people. one case convinced the police there was a killer in the hospital. it involved the family with twins, whose son died back in august 2015. 2a hours later, his twin brother also became very unwell. so, one of the nurses had come and knocked on our doorand said, you know, he's not, he's not well, he's not well at all, his heart rate is really, really high. what's your first thought? it's happening again. thought it was happening again and, i said to my husband, please, not again, we... we can't do this again. this can't be happening.

it's almost bang—on 24 hours since, since our other son had died. thisjust can't be happening. and so i went and i sat with him all night. his heart rate was absolutely through the roof and, you know, it didn't come down, and i wasjust like, just come down, you know, and i'm almost trying to will the machine, you know, bring his heart rate down, make it ok. this time, the medics managed to save her baby. but the parents say he was badly harmed by the trauma. he's got severe learning difficulties, he's got a lot of complex needs.

is it your belief that that's connected... yes. ..to what happened? yes. directly as a consequence. and he's living with it. in early 2018, dr brearey was reviewing the baby's notes for the police. he found evidence the infant had been poisoned. a blood test showed the baby had high levels of insulin. it had been missed by a junior doctor. it was the first sight i had of this result and it made me feel sick, actually, thinking about it. there was a baby case in front of me in which it was quite clear that this baby had been poisoned by insulin. and the nursing record supported the fact that lucy letby was present,

on shift at the time. the body produces insulin naturally. when it does, it also produces a substance called c—peptide. most medical experts agree, if there's hardly any c—peptide, then the insulin cannot be natural. if you measure very high levels of insulin with very low levels of c—peptide, then it can only be the case that the insulin was not made by the body, so that would be objective evidence that there has been, that somehow insulin has been administered to this baby. it wasn't produced by the baby. and it can't have - happened accidentally? no, this would not happen accidentally. the review of patient records suggested a second baby had also been poisoned with insulin. the review of patient records suggested a second baby had also been poisoned with insulin.

the crucial evidence had been missed for more than two years. it looked like a baby killer had been left on the unit. was this a significant missed opportunity that when those lab results weren't really flagged at the time? yeah. do you think that was a missed opportunity? yes, yes. in an ideal world, you'd hope that the lab would flag it so it would be reviewed by somebody senior. that didn't happen. it's been said there's no smoking gun in the lucy letby trial, - but these insulin cases get close to it, do they, for you? - they were a smoking gun for these babies for sure, and i don't have any doubt that lucy letby harmed these babies. the insulin cases were a real

milestone in the investigation. we were shocked, really to the core, to find that a baby had been injected with insulin. it's another layer of surprise, i suppose, as to the depths that lucy letby went to. the other cases were less straightforward. but evidence from medical experts indicated all the babies had been harmed intentionally. now, in a couple of the cases, the prosecution say this has been been poisoning with insulin. in a couple of the cases, it's by force—feeding these children milk. in several of these cases, it's through injecting the child with, with air, air bubbles that, you know, it can cause great harm to, you know, even adults, but to vulnerable babies, it's,

it's a life—threatening situation for them. evidence suggests there was a killer on the unit. but how do we know it was lucy letby? this prosecution document shows which nurses were on duty when babies collapsed or died. some were only present on one or two shifts. some were there on six or seven. but lucy letby was always there. she was working on the unit during every single one of the 25 suspicious incidents. hello, lucy is it?

yeah. in 2018, lucy letby was arrested for the first time. if you just take a seat in there for me, lucy. i'll move that seat forward a bit. i'vejust had knee surgery, so... 0h, right, 0k. we woke up at six o'clock . in the morning to our phone, and it was the family liaison - telling us they'd arrested somebody on suspicion of murder — a health care worker — l and he came, and he had a conversation and - he said, lucy letby. the absolute shock.

i'd almost, in my own mind, - been like, "oh it's someone we don't know and it's someone _ in the background who's done this awful thing," and never in a million years did i think it would be - someone that we, we feltj we had a connection with. the shock of that. the shock of that was just unreal — unreal. i lucy letby is clearly the person who, who keeps things. she kept obviously medical records, she kept handovers sheets, she kept electronic devices and photographs. so, she kept diaries, very detailed diaries and notes, which surprised me. because lucy letby would have been aware that we were going to come and speak to her at some point. the police found lucy letby had been

searching for information online about the parents of some of the dead babies. in one case, on the anniversary of their baby's death, they also discovered a note inside her diary. it says "i haven't done anything wrong". but it also says "i killed them". look, you see, it says "i... "i killed them. i'm not good enough. i'm evil. i did this." well, it seems like a confession, but it might be she's saying "it is alleged i killed them. it is alleged i am evil, i did this." do you know, i worked on a number of murder cases whereby you get people writing strange notes all the time.

it's evidence of there perhaps being underlying stress, mental health problems. it's not necessarily evidence of guilt. i just think this is the ramblings of somebody who's under extreme psychological pressure. there may be strong circumstantial evidence against her. but neither the police nor the prosecution have offered a motive. and no one has ever seen lucy letby harming a child. lucy was arrested and released on bail, and then she was arrested again and, at that point, i think the police had spent three years trying to build a case, to find someone culpable, to find someone to blame. did you question, at that point, if it could be something - she was capable of? of course, it run... it goes through your mind for an instant, where you think,

"what do the police know that i don't know?" but in that instant, it's gone in a second, because it's replaced by "i know lucy, i've grown up with lucy." you've spent time interviewing her. what do you make of her? she's a difficult one to work out. because she's emotionless. she wasjust very clinical in her answers. so, she was comfortable, she'd go through medical notes, she would talk to us, she was cooperative, she engaged. but there was no empathy or, or sympathy with

a nurse accused of murdering seven babies has been giving _ evidence at her trial. morning, busy day. i've got quite a few calls to make. in manchester, the defence case has started. and lucy letby is giving evidence. there was complete silence in court as lucy letby spoke in a clear voice, looking directly at the jury and sitting just yards away from the parents of some of the babies she's accused of attacking. this is the day i've been waiting for for months,

because we've had all of these accusations laid out in court, and today is the moment where we get to see her and hear her directly. you know, she's going through the detail of the medical notes, and she's being asked about that quite closely, and she's dealing with those questions in a very assured way. she comes across as a bit mousy, a bit normal. you can't possibly marry that with the enormity of what she's being accused of. lucy letby says she was always on duty as she was willing to do extra shifts, and was trained to care for the sickest babies. and that staff shortages and poor maintenance had left the unit unsafe. but after seven days in the witness box, the pressure is starting to show.

i think she's starting to crack. pressure's getting to her. we had a break this morning. we weren't supposed to have another one until lunchtime and then, and then she asked for one. she said, "i need a break" and you can tell that she's getting stressed. from the start, she's told her friends not to attend court. we've been in contact through writing letters but she's not been able to have any updates about all of her godchildren, because she's not allowed to be told about any information pertaining to children. have all of lucy's friends stood by her? yes. we know she couldn't have done anything that she's accused of. so, without a doubt, we stand by her. i've grown up with lucy, and not a single thing that i've ever seen or witnessed of lucy

would, you know, let me for a moment believe that she was capable of the things she was being accused of. you seem utterly unshakeable on this, but isn't it possible i she's, she's fooled you all? unless lucy turned around, and said, "i'm guilty", i will never believe that she's guilty. have you ever thought that there could be some other explanation for all of this, and that lucy letby is innocent? well, that was the journey we went on in the first year, before we finally asked her to be removed from the neonatal unit. that was a year of looking for all that alternative explanations. and... we excluded all of those things until we got down to one point, which was lucy letby. i want her to be locked up and i never want her to come out

again, because what she's done has changed the course of our life for ever. i think she's a hateful human being. i think she's taken everything from us — absolutely everything. jurors in the murder trial of hereford nurse lucy letby have retired to considered their verdict. ms letby denies murdering seven babies and attempting to kill ten others. you can feel the tension every day here. no one knows if this will be the day when the jury returns its verdict. the trial has been running for ten months. it's five—and—a—half weeks since the jury was sent out. now, they've reached their verdict. she's guilty. the jury has found lucy letby guilty of murdering seven babies and attempting to murder another six. they found her not guilty of two

attempted murder charges, and couldn't decide on a further six. but they have clearly found that letby is one of britain's most notorious killers. and there's a statement from the hospital: i speak i cannot imagine how the families in this case feel today. ijust open the case of this verdict brings all of them some peace of mind for the future. and that we've answered some of the questions that they were looking for. and there's a statement from the hospital. i speak for the whole trust when i say how appalled we are at lucy letby's crimes. we are extremely sorry that these crimes were committed at our hospital, and our thoughts continue to be with all the families and loved ones of the babies who came to harm or who died. we cannot begin to understand what they have been through.

the jury was only asked to consider seven murder charges. we've discovered that 13 babies died during lucy letby's last year on the neonatal unit. she was on duty for every one of them. the police investigation is going wider still. two babies died while lucy letby was training at liverpool women's hospital. are you looking at other cases? yes, i'm sure the public would expect us to, to look at the entire footprint of lucy letby's career, all the way through lucy's placements at chester and at the liverpool women's hospital. and could that result in, in further charges down the line? possibly. we have informed a number of parents already that we're investigating their child,

and they're being supported. the countess of chester hospital is under new management. the unit no longer cares for such sick babies, and there's only been one death in seven years. can expectant mothers coming into the unit have confidence? i think those parents can expect as high a level of care on our unit than any other unit in the country, really. it's upsetting, this. mm. we've got through a particularly hard time, and... i think we owe it to the families, for them to know that the staff care.

lucy letby now faces years in prison for harming babies in her care. but why did she do it? what turned a likeable, fun—loving nurse into a serial killer? i don't think we know why, why lucy letby has done this. and that's really difficult to take. i can't imagine how a parent must feel. it'sjust beyond your- imagination that somebody's on a ward, killing babies. it's unbelievable. she had everything going for her, and then starts killing babies. what happened ? i think it's something that we'll never know,

and i think, as a family, we need to make our peace with that.

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live from washington, this is bbc news. bracing for impact: hurricane hilary heads towards mexico and the us south west. a tale of two wildfires: canada works on evacuations, while offcials in hawaii face more questions over their handling of the response. and in ecuador, voters go to the polls on sunday in a runoff overshadowed by violence. hello, i'm carl nasman. we want to start the programme with three weather events — thousands of miles apart, involving fire and water,

and disrupting the lives of local communities. in a moment, we'll have the latest on the evacuations in canada, where a town of some 20,000 people is scrambling to safety. then we'll focus on the aftermath of the hawaii wildfires, and new questions over how the blazes started in the first place. but we start in california, where for the first time ever, a tropical storm could hit the southern part of the state. right now, hurricane hilary is a category four storm. it's expected to make landfall in mexico in the state of baja, california, seen here, on saturday. it will likely then downgrade to a tropical storm before hitting southern california, with san diego and los angeles in the path. you can see, prepaparations are already under way there including working to shore up hillsides. officials are worried about landslides and major flooding. the last tropical storm to hit california was in 1939 — over 80 years ago. this map shows the predicted path this storm might take. as of early friday, the centre of the hurricane

was located roughly 400 miles — that's 6113 kilometres — south