this is bbc news, i'm carole walker. the headlines at 11:00pm: a new home secretary and a personal promise from sajid javid as he pledges to address the windrush scandal, taking overfrom amber rudd, who stood down yesterday. the windrush generation has been in this country for decades, and yet have struggled to navigate through the immigration system. this never should have been the case, and i will do whatever it takes to put it right. israel's prime minister claims he has conclusive proof that iran has a secret nuclear weapons programme. two bomb blasts in kabul kill at least 25 people and injure dozens more. asda and sainsbury‘s claim that grocery prices will fall if their planned merger gets official approval. warning from scientists as a study

reveals a huge antarctic glacier is melting and at risk of collapse. and on newsnight, a dramatic 2a hours in politics. tonight we will ask whether the prime minister, having lost the home secretary, will now lose her immigration policy. is this a turning point? good evening and welcome to bbc news. sajid javid has spent his first day at the home office, replacing amber rudd, who resigned as home secretary last night over her handling of immigration policy. mrjavid said his most urgent task was to ensure that caribbean migrants, members of the so—called windrush generation, were treated with fairness and decency. mrjavid, whose parents came to britain from pakistan in the 1960s, said he was personally committed to helping those who had been mistreated. our political editor

laura kuenssberg reports on the day's events. 8:30am — off to work. but where's the office? good morning. half an hour later, at 9:00am, sajid javid took the call that gave the answer. the new home secretary. will you be able to get a grip on the home office? with orders from number ten for one of the biggestjobs, with some of the most brutal pressure. but it is a messy takeover for this former banker—turned—politician. sorting out the windrush fiasco — top of the list. like the caribbean windrush generation, my parents came to this country from the commonwealth in the 1960s. so, when i heard that people who were long—standing pillars

of their community were being impacted for simply not having the right documents to prove their legal status in the uk, i thought that it could be my mum, my brother, my uncle, oi’ even me. so i want to end by making one thing crystal clear. we will do right by the windrush generation. he's in because she's out — amber rudd's cabinet career sunk by six words. we don't have targets for removals. except they do. targets that the prime minister admitted existed on her watch. shouldn't you be taking personal responsibility, not amber rudd? this is your "hostile environment". amber rudd was very clear about the reasons why she has resigned. that was because of information that she gave to the house of commons that was not correct. if you look at what we're doing as a government,

and have been doing over the years as a government, what we are doing is responding to a need that people see for a government to deal with illegal immigration. the new home secretary's first day as an mp was only in 2010. well, it really is like being at school again, on the first day. made a minister then promoted to the cabinet by david cameron. but, as business secretary, he faced calls to quit when the indian—owned tata steel company was up for sale. and, while in charge of housing, he has been under pressure over the promises made after the grenfell fire. labour warns the appointment will be meaningless unless there is a change in how the office works. i look forward to the new home secretary showing some interest and some determination to ensure the home office works efficiently and effectively, because at the moment it doesn't. james brokenshire returns from illness to replace sajid javid

at the housing department. i'm delighted to have got this new responsibility. for him and mrjavid, with near—impossible tasks ahead, a brief moment to enjoy day one. but i haven't called my mum yet, and i will do that later, when you give me a moment. he is inheriting big problems, and no home secretary can be sure of avoiding accidents that may come. laura kuenssberg, bbc news, westminster. in one of the worst days of violence in afghanistan this year, 37 people have died and many more injured in a series of attacks, including twin suicide bombs in the capital, kabul. the first was detonated by a motorcyclist near the headquarters of afg hanistan‘s intelligence service. the second blast was reportedly by a bomber disguised as a cameraman. the attack appeared to target journalists. these men, all afghans, were among them. the islamic state group says it carried out the attacks. a separate attack in

afghanistan's khost province has claimed the life of a bbc journalist. ahmad shah, who worked for the bbc‘s afghan service, died of gunshot wounds shortly after being attacked. the 29—year—old had been with the bbc for around a year and was engaged to be married. the israeli prime minister, benjamin netanyahu, claims that his country has new and conclusive proof that iran has been hiding nuclear weapons activity. mr netenyahu alleged that 55,000 pages of material stolen from tehran by israeli intelligence agents showed iran had been deceiving the world since signing the nuclear deal in 2015. after signing the nuclear deal in 2015, iran intensified its efforts to hide its secret nuclear files. in 2017, iran moved its nuclear

weapons files to a highly secret location in tehran. this is the shorabad district, in southern tehran. this is where they kept the atomic archive, right here. few iranians knew where it was, very few, and also a few israelis. now, from the outside, this was a very innocent—looking compound. but from the inside, it contained iran's secret archives, locked in secret files. actually, they're a little bigger than this, 0k? a few weeks ago, in a great intelligence achievement, israel obtained half a ton of the material inside these vaults. iran described the claims as a rehash of old allegations already dealt with by the international atomic energy agency, with iranian state tv accusing

mr netanyahu of baseless accusations and propaganda. britain‘s second— and third—biggest supermarkets, sainsbury‘s and asda, have confirmed they are to merge. management says the deal would benefit both shareholders and customers. they also promised that no stores would close. the deal, worth £10 billion pounds, needs approval from the competition and markets authority before it can go ahead. our business editor simon jack takes a closer look. lower prices for everyday items — that is the promise on offer to customers of both sainsbury‘s and asda, as they laid out their plans for one of the biggest retail mergers in decades. the prospective boss of the new giant said its increased buying power would mean a better deal for customers. ultimately, we'll pass those benefits back to our customers, in the form of lower prices, and what we're talking about today is that we'd expect the price

of everyday items, not all items, but everyday items, in the round to fall by 10%, and that's what we would aim to do. a combination of the second— and third—largest supermarkets will create a retailing powerhouse. currently, the two companies have a total of 2,800 stores in the uk, employing a giant workforce of 330,000 people. together, they would account for over 31% of the uk grocery market, knocking long—time leader tesco into second place. sometimes attack is the best form of defence, and many see this bold move as a response to threats to the marketplace from the discounters aldi and lidl, from tesco's move into wholesaling by buying booker, and of course amazon, which has set its sights on the uk grocery market. the question is will this "bigger is better, bigger is safer" strategy be enough to convince

competition authorities, suppliers and, of course, customers? both brands will continue to trade side by side, although competition authorities may force some sites to be sold, when they dominate certain areas, like here in keighley, where customers are unsure how it will work. i think it's a bit strange, actually, because they're completely at different ends of the market. ijust wonder which way they are going to go. i'm not quite sure how it is going to work, to be quite honest, especially with them being so close to each other. and in most towns, they do have both, don't they? there is another bold promise. although some may be sold, no stores will be closed or in—storejobs lost. that has left some suppliers fearing that they will bear the brunt of any cost savings. if there's no store closures and no cost—cutting by sainsbury‘s or asda, it's the suppliers who are going to have to pay the difference. and that will mean that suppliers will have to consolidate, suppliers will have to lose jobs, suppliers will have to close factories, and that will leave less choice for consumers in the end. sainsbury‘s share price jumped 16% on the day. in an unguarded moment between interviews, mike coupe was filmed singing a song he later apologised for as unfortunate,

and sainsbury‘s said had no wider meaning. on a serious note, this deal is far from done. it will attract intense scrutiny from the competition watchdog, but its sheer audacity is proof of how much the retail landscape has changed. simon jack, bbc news. the thwaites glacier in antarctica is a glacier the size of britain, and it is melting at an increased rate, causing sea levels to rise. britain and america are sending 100 scientists to assess the state of the glacier. they say that if it were to collapse entirely, the rise in sea levels would be rapid and could have dramatic consequences globally, as our science editor david shukman reports. antarctica is changing. scientists capture the moment that vast chunks of ice break into the ocean. there is so much ice here that, even ifjust some of it melts, sea levels will rise around the world.

so the urgent question is how rapidly the glaciers, the great streams of ice, are moving. satellite pictures already reveal that one of the biggest of them, thwaites, is shedding huge blocks of ice. if the whole lot went, the sea would end up nearly a metre higher. this matters for the millions of people who depend on sea defences to keep them safe, from the thames barrier in london to walls of mud in bangladesh. the key is predicting how fast the sea will rise. we found, definitely, a place that really could uncork the genie, in terms of sea level rise, at a much shorter timescale than has been talked about before. things that would really make it difficult for coastal planners, cities, countries, to react fast enough. this latest research will focus on the western edge of antarctica, where the massive thwaites glacier, one of the largest on the planet, flows into the ocean. now, scientists already know that warm seawater is working its way under the front of the ice,

melting it from underneath. but they don't yet know whether the ice will totally collapse and raise sea levels. so, over the next five years, they will be measuring the ice from the air, checking the glacier‘s thickness by drilling into it from the surface. and also using robot submarines to explore what's happening to the ice underwater. the submarines will be venturing into a hazardous world, but what they find out will help improve the forecasts for the future of the sea level. professor karen heywood is leading one of the teams that will deploy the subs. it's going to be very scary for us. we're going to be very nervous when we send it under the thwaites glacier for the first time. we will be crossing our fingers that it comes back safely. but it's thrilling, as a scientist, to get data from somewhere that nobody‘s ever measured before. but conditions will be unbelievably tough. the glacier couldn't be more remote. getting scientists there

will involve one of the largest operations ever mounted in antarctica, and the teams camping on the glacier will have to endure notorious weather. but, if they can help predict the rise of the oceans, they say it's worth it. david shukman, bbc news. that is a summary of the news. newsday is coming up at midnight. now on bbc news, it is time for newsnight with evan davies. rarely has a new home secretary arrived in post better able to call the shots. but will he be good, bad or ugly? he owes theresa may little, he's about to get a close—up view of all her mistakes at the home office, and he is the man she needs to detoxify the party's image with minority communities. will he now try to reshape her immigration policy? will the reshuffle reshape the direction of her government? sainsbury‘s slogan is live well for less, the same thought as asda's — save money, live better. no wonder the two want to merge.

we'll ask if it's actually a good idea for them, orfor us. also tonight — the journalist who investigated those deaths of russian mercenaries in syria was himself later found fatally injured. was his death really an accident? and on internationaljazz day, we have courtney pine. music. hello there.