in shetland with snow showers continuing. on monday, milder air spilling in across most areas as we get a stronger west to south—westerly wind. the weather front in the north is crucial, the boundary between the mild air and the cold air sitting across northern areas. snow in northernmost parts of scotland, rain, wetter in northern ireland, wales, north—west of england. dry towards the south of england. temperatures of 7—8, could make double figures in belfast on monday. the milder, cloudy wetter weather could push southwards during the evening and overnight, clearing away for most areas in time for tuesday. briefly, colder air returning and perhaps a frost in scotland, northern england, perhaps northern ireland to begin. more cloud to the south, rain and drizzle hanging on to the south—west of the uk, temperatures reaching ten. eight in london.

further north, colder at 4—6c but at least some sunshine. frost developing early in the night before the weather fronts come back in from the atlantic bringing milder air on wednesday and more cloud and outbreaks of rain eastwards to most of the uk. the rest of the week looks largely dry. last week these temperatures were around 1—ac, this week will be much milder.

this is bbc news, the headlines: the nhs is facing "the worst crisis in living memory", according to england's chief medical officer. chris whitty says hospitals could soon be overwhelmed — leading to avoidable deaths. it comes as asymptomatic testing in the uk is ramped up and more than half a million people over the age of 80 are invited to mass vaccination centres — with the government pledging vaccines for the rest of the adult

population before next winter. rescue teams in indonesia have found the black box flight recorders of the boeing passenger plane that crashed into the sea shortly after takeoff. 62 people were on board. president trump will face impeachment proceedings this week for the second time — accused of inciting the storming of congress. and, a special report from south africa, following the people committed to saving one of the world's most endangered and trafficked creatures — the pangolin. now on bbc news, witness history. in this edition we hear from the man who invented the polio vaccine and exmaine how hiroshima's trees have become a symbol of survival. hello and welcome to witness history in nairobi, with more remarkable

moments from the past as told by the people who were there. today, we present five of our most memorable recent stories. coming up, how hiroshima's trees became a symbol of survival. plus, revealing the truth about a civil war atrocity in el salvador. the algerians who fought with france against independence. and the man who invented the revolutionary prosthetic leg. but first, with a remarkable global effort to create covid—i9 vaccines, we look back at a previous world—changing vaccination breakthrough. in 1955, a group of us scientists led by doctorjonas salk announced the discovery of the first polio vaccine that saved millions from death and disability. his son, doctor peter salk, spoke to us about his father's extraordinary achievement. back in the 1950s, people were overjoyed at the fact that here is a vaccine that is going to protect us from this terrible,

frightening scourge. polio is a disease that is caused by a virus that gets into a person's mouth. the virus grows in the intestinal tract and then gets into the bloodstream from which it moves to the brain and the spinal—cord, kills the nerve cells that signal the muscles when to move, and because of that causes paralysis in the muscles. my father, when he was young, just knew that he wanted to do something to help humanity. the vision that he had at that point was that he would then go into medicine. he got a knock on the door from the national foundation for infantile paralysis, would you be willing to participate in a typing programme to determine how many different immunological

types of polio virus there are? my father leapt at the opportunity. this would be drudgery, in terms of the kind of work that was done, but it was an opportunity of creating a vaccine against polio. the worst year was 1952. there were 58,000 cases of polio. nobody would ever know when was the epidemic going to come? when was it going to strike? this disease caused a huge amount of fear. there was a lot of pressure. every year there were these devastating epidemics. first there were the studies that were done on animals in the labratory, that all pointed in the right direction. then my father undertook some preliminary tests in children who were at a home for crippled children outside of pittsburgh. these were kids who had already been affected by polio.

the early studies had gotten far enough that he knew that this vaccine was going to work. the day that he came home from his office bearing syringes and needles which he boiled on the stove in one of our kitchen pots to sterilise, loaded up the experimental polio vaccine that he was working on and then lined us kids up and administered the injections. i'm going to say to you, i have no words in which adequately to express the thanks of myself, all of the people i know, and all 164 million americans, to say nothing of all the other people in the world, who will profit from your discovery. i am very, very happy. there was absolute jubilation. church bells rang, factory whistles blew. it was such a relief.

the polio vaccine had a huge impact on society. we have moved into a situation where people are feeling what dangers vaccines might have in and of their own right. it's important to be aware of the problems that can take place with vaccines, but it is disadvantageous to be so hyper reactive to the whole notion of vaccination that the baby gets thrown out with the bath water. doctor peter salk on a vaccine that change the world. that changed the world. now, 75 years ago, in 1945, the first atomic bomb was dropped on the japanese city of hiroshima. hundreds of thousands of people were killed and injured, yet, amid the devastation, remarkably, some trees in the city survived and they have since become a symbol of hope and recovery around the world.

translation: these are the real witnesses. these trees have seen everything. explosion translation: at 8:15am on august the 6th 1945, an american bomber plane dropped an atomic bomb on hiroshima. it exploded 600 metres above the hospital. it didn't explode on the ground, but in the air. i've heard that the bomb was dropped from this height to kill as many people as possible.

the radiation burnt all living things in hiroshima, particularly in the two kilometre radius of the epicentre. people were burnt alive. this garden is about 1.5 kilometres from the epicentre of the bomb. i heard from many people that at the time there was no colour in hiroshima. there was only black, white or grey. some people said that no plants would grow here for the next 75 years. everybody believed that rumour. they thought this town was dead. at the time, the trees looked like charcoal. a stick of charcoal, like this. but on some of the trees, buds emerged. when people saw that the green buds had come out, they thought they could survive as well.

it was comforting. i can just imagine the vividness of the tiny green bud in that colourless world. it must have given people some comfort and hope. my friend and i established the green legacy hiroshima project as co—founders. green legacy hiroshima tries to plant the seedlings of these trees in places with nuclear power, places under the nuclear umbrella, and those places who have experienced various natural disasters. we hope the trees can deliver the message that we as people have the power

to recover and survive. trees have a magical power to tell each person what they need to hear. they speak to each human being as well as the whole of humankind across the world. that was the co—founder of green legacy hiroshima. what a remarkable story. and now a story about the daring to speak the truth to power. in the 1980s, el salvador was in the grip of a civil war. rebels were fighting against a us—backed military regime. one night in 1989, sixjesuit priests were dragged from their beds and murdered, along with a housekeeper and her teenage daughter. the government blamed the rebels, but one woman risked her life to tell the world what really happened.

the priests‘ funeral took place at the university where they were murdered. they were el salvador‘s leading left—wing intellectuals. thousands came to mourn, not just for the dead men, but because they symbolise the hope that el salvador might become a country one day where power came from the ballot box and not from the barrel of a gun. translation: the priests were always on the side of the poor. that's how they were. it still hurts to remember them and to remember what happened. i will keep telling this story until my dying days. i can never forget it. the government troops are fighting the biggest guerrilla offensive since 1981. the rebels appear to have moved into the capital in force and have held positions for more

than 12 hours. translation: there were soldiers and rebels shooting all over the place. we couldn't go out and food and water were running low. i was very nervous. i worked as a cleaner at the jesuit university. i called one of the priests and asked if we could come and shelter on the campus with my husband and daughter. he said, yes, of course, come. it all happened just after midnight. we were awoken by the sound of gunfire near the entrance to the university. i got up and went to an open window to look out. i could see the shadows of men at the entrances of the rooms where the priests slept. they were soldiers.

i heard one of the priests calling out that it was an injustice, a disgrace. then i heard shouting and more shooting. after that, there was just silence. the killing that has caused the greatest outrage is the murder of the six catholic priests dragged from their beds and shot yesterday morning. translation: in the morning, we went to see what had happened. even from a distance, you could see the bodies of the priests laid out on the grass. in a small side room, there were two women lying dead in an embrace, full of bullets. they were the housekeeper and her daughter. the soldiers didn't want to leave any witnesses. the government said it was the guerrillas who killed them. but i said, no, it was the army,

and that i had seen the soldiers. they didn't like me saying that. after that, i was taken with my husband and daughter to the airport and put on a plane. the jesuits said that they couldn't protect me in el salvador. when i got to miami, i was interviewed for a week by the fbi. they wanted me to change my story. eventually, i told them, you can believe me or not. i really don't care. i guess that i was there for a reason that night. another person might have kept quiet and not spoken out. but as god says, you have to do something in this life. and i did something.

what a remarkable woman. two soldiers were eventually prosecuted for the murder, but were later released under an amnesty law. remember you can watch witness history every month on the bbc news channel or you can catch up on our online archive. just search for bbc witness history. next, a part of african history that is often overlooked. in the 1950s and ‘60s during algeria's bitter war of independence against france, thousands of algerians actually fought on the french side. for that, after the war, many would pay a high price. this person was one of them. translation: the harki localforces were on the side of the french army in algeria's independence war. we gave everything for france but what we didn't know was that france would abandon us.

as tension rises in french north africa, france arms her algerian supporters for defence against rebel raids. in this province, weapons are being handed out personally to muslim recruits, where hundreds are being enrolled daily. translation: i was about 17 and a half, 18 years old at the time. you had to choose between france and the rebels. my father had been in the french army and had fought in world war i. my brothers were also in the french army. so i chose france. translation: i was proud of what we did.

proud of saving france. proud of serving france. we were always sent out in front of the french troops. if there was an attack, the harki would be the first to die. we had to get rid of the fighters who are terrorising the population. translation: we always knew that one day algeria would gain its independence. what general de gaulle should have done was take all the harki and theirfamilies to safety in france. but in 1962, the french disarmed the harki and left us defenceless. the other side took advantage of this and began to round us all up.

they took me to a barracks where there were about 50 other harki prisoners. there was blood everywhere. they stripped me naked and started torturing me with electric shocks. each time a new group of soldiers came on shift, they began again. the same thing every day. the fln even made us dig our own graves. some people were thrown in alive. some were thrown into the river. the jackals did the rest. i was arrested onjuly the 8th, 1962. i escaped in september the 10th, 1962.

it took me a long time to feel welcome here in france. i decided to change my name and to convert to catholicism. i wanted to make a fresh start. i could say that i was born under a lucky star and that i am lucky. but not all the harki were so lucky and that is the fault of france. finally, a story about a remarkable invention built out of adversity. as a young man, this man lost his foot in an accident and designed a prosthetic leg to allow him to keep running. the invention revolutionised the world of parasports. when you lose body part, it's different from any other experience because it's gone.

it'sjust gone. that was the hardest part, knowing that it was irreversible. i had my accident in the spring of 1976 when i was 21. winter had just broke and it was now time for spring water skiing. i havejust taken a big cut to the left and the boat quit. then, all of a sudden, over my right shoulder, i turn around, and another boat came right at me. and the odds are, my ankle's that wide, and that's what it hit. the propeller. had i not had a wet suit on, i would've bled out. major arteries were cut. but my knee was bent, the wet suit was tight, itjust stopped blood flow. they put a cast on the stump. on the bottom was a pink, rubber foot.

i was sitting there, looking at my pink foot and ijust felt like my life was gone. the artificial limb, especially if it is a leg, is the most important thing in their lives. they ought to get, and it seems now that they will get, the best that technological modern skills can provide. the question is, when? i knew that there was a better way. several years prior they had just put a man on the moon. so my early attempts at creating something that would spring and push off was, you know those insoles on the side of your shoe? that was my first concept. let's build one of those. those early ones weren't too bad. i had a block of foam in the toe and heel. but then i got blessed. one of the world's leading aerospace graphite engineers helped me. that night, we drew up the drawing of what the leg was to look

like and within two, maybe three weeks, i built a leg and i attached it to my sock. i ran down his hallway, i mean, fast. that was freedom. that was a real inner freedom. i probably built 50, maybe 60, more legs. different types, different arrangements, broke them, fell down. we finally launched our first foot. the first carbon graphite, energy storing running prosthesis ever. so, if you look at the structure, it is millions of tiny little hair—like fibres. those fibres stretch just like our tendons do. so that energy can be stored in those fibres. that's how we came up with the c—shape foot.

my foundation's name is called second wind. i'm involved in developing a foot for landmine survivors. they have to go to work. they are labourers, they're planting fields. they don't have the luxury of sitting down. for asia, a lot of people work with rice. you can't wear a standard foot in water, they rot. in afghanistan, iraq, they are on rocky hillsides going up and down mountains. we built a design that has increased function, decreased weight, and increased strength. the foot has to be able to endure all kinds of different climates. we are calling it the world foot. the world foot for all countries, all peoples, everywhere. when i think of all the amputees in the world, that i can actually share that, there was never a greater joy than that for me. that is all for this

episode here in nairobi. you'll be back next time with more first—hand accounts of extraordinary moments in history. but for now from me and the rest of the team, goodbye. hello, this morning was not as cold as yesterday morning, but it has started frosty and foggy in some parts. but through the day we are looking at milder air to push in. with that frost and fog lifting across the south, it may brighten up across the south, it may brighten up a touch this afternoon. but generally a lot of cloud. we will see the rain turning heavier in western scotland, temperatures here

reaching eight degrees, i think five 01’ reaching eight degrees, i think five or six will be typical. maybe lower in the south—east. a cold day here, but not as cold as yesterday. for many, overnight we keep cloudy skies with some rain and drizzle. wetter in western scotland, threatening some flooding with the snow melt. for most parts temperatures just above freezing w the cloud thinner in the south—east we could see a bit of frost here and we have still got cold weather in shetland, with some snow. on monday milder air spilling in with a stronger west to south—westerly wind. that front in the north is crucial, it is the boundary between the mild and cold air. so we will see some snow in northern scotland. rain elsewhere. wetter in northern ireland, into wales and north west england. dry to the south—east of england. maybe some sunshine. temperatures of seven 01’ some sunshine. temperatures of seven or eight degrees. could be double figures in belfast on monday. that

milder cloudy, wetter weather will push south over night to clear from most areas in time or tuesday. and that means briefly we will find colder air returning and we may have a frost to start with in scotland, northern england and northern ireland. there is more cloud to the south and we still have rain and drizzle into the south—west of the uk with temperatures reaching 10 degrees. eight in london. further north it will be colder, four to six celsius. but at least there will be some sunshine. we may well find a frost developing early in the night, before these weather fronts come in, bringing milderairon before these weather fronts come in, bringing milder air on wednesday and bringing milder air on wednesday and bringing more cloud and rain. the rest of week is largely dry. last week, these temperatures were around one to four celsius. so for this week it is going to be much milder.

this is bbc news, with the latest headlines for viewers in the uk and around the world. england's health secretary has given a new warning that the national health service could soon be overwhelmed by the spread of coronavirus. it echoes concerns from england's chief medical officer, who says if hospitals are overwhelmed, this will lead to avoidable deaths. we can all do something to help, stay at home. every time you flex the rules, that could be fatal, and we all have a part to play. the labour leader, sir keir starmer is calling on the government to bring back daily briefings, to help reiterate the "stay at home" message to the public.

we have had mixed messages, i'm afraid, which