this is bbc news. i'm rachel schofield. the headlines at "pm: the public inquiry into the grenfell tower fire opens as the man leading it promises to get the truth. it can and will provide answers to the pressing questions of how a disaster of this kind could occur in 21st—ce ntu ry disaster of this kind could occur in 21st—century london. the bank of england warns interest rates may go up in the coming months for the first time in a decade. at least four people are arrested after disorder breaks out at arsenal's europa league match against cologne. and, on newsnight, are we witnessing the collapse of bitcoin? china stamps its authority on all the digital currency‘s exchanges as a top banker calls it a fraud. and we report from the front line of the demilitirized zone between north and south korea. good evening, and

welcome to bbc news. at least four people have been arrested after what what police have described as disorder at arsenal's europa league match against fc cologne tonight. up to 20,000 german fans are in london for the game, most without tickets. the kick—off was delayed by an hour, and has only ended in the past few minutes. it's the first time in 25 years cologne has played in an international club competition. before the game, they were led by police through the city centre, with reports of bottles being thrown. only 3,000 had tickets, and so the situation outside the stadium became ever more difficult, with those extra cologne supporters either trying to get in or stopping others doing so. inside, it was clear many had

managed to buy tickets from touts, with arsenal fans getting in touch with the bbc to say they were surrounded by german supporters, with others climbing over barriers to join those in the away end. 0ur correspondent dan johnson has been there. the metropolitan police tell us that there were four caress here, four arrested on suspicion of public offences, after extra officers needed to attend emirates stadium this evening because of disorder inside the stadium. there was a huge buildup of fans outside the ground, particularly cologne fans, who were he in vast numbers. not all of them could get in. it appears some of them had tickets in the arsenal area of the ground, so police had to be very careful about how many fans they were letting into each section of the ground. it also time, it

meant kickoff was delayed by an hour and some fans were in the stadium fighting with stewards. so four arrests and a huge police operation in place. as you can see, fans are leaving, arsenal having won the game, so those cologne fans probably subdued on their way home now, disappointed with their team's performance tonight. a huge police operation involving riot police, there are helicopters flying above, mt police officers on horses, and certainly there will be questions after this came about the ticket sellers and how so many fans were able to get tickets and fine seats in the arsenal areas of the ground. the chairman of the public inquiry into the grenfell tower fire, which killed at least 80 people, has promised that it will provide answers to how a disaster of this kind could occur in 21st century london. sir martin moore—bick said he recognised the anger and betrayal felt by those affected, but would examine the evidence calmly and rationally. but already there's been criticism from some of the victims‘ families over how the inquiry is being handled, as our special correspondent lucy manning reports.

the tower is still charred, the grief still raw. victims are unidentified, and questions still unanswered. for so long, those who lived in grenfell warned it wasn't safe and no—one listened. now, they want to hear from the inquiryjust who was responsible. ahmed chellat is on a journey to the opening of the inquiry today, but he hopes eventually to justice. i would like him to find out the cause of the fire. he lost his brother—in—law, sister—in—law, two nephews and a niece in the fire. eight—year—old mehdi, just identified yesterday, eight—year—old mehdi, just identified yesterday. they are still waiting to find the remains of 15—year—old nur huda. what do you want the inquiry,

in the end, to be able to do for yourfamily? well, we're not going to have them back, that's for sure, but prevent it from happening again. prevent it from happening again. i mean, it will be the hope of the family and everybody. justice for grenfell will take some considerable time. and inside the ornate room a few miles from the fire, the chairman, sir martin moore—bick, opened the inquiry with silence for the victims. thank you very much. but it certainly isn't silence those who escaped from this tower want, but questions asked and answers given after so many died and so many lost everything. the inquiry cannot undo any of that, but it can and will provide answers to the pressing questions of how a disaster of this kind could occur in 21st century london, and thereby, i hope, provide a small measure of solace. i'm well aware that the past few

months have turned the world of those who live in north kensington upside down and that former residents of the tower and other local people feel a great sense of anger and betrayal. that is entirely natural and understandable, but if the inquiry is to get to the truth of what happened, it must seek out all the relevant evidence and examine it calmly and rationally. as he finished, a barrister advising some of the survivors stood and tried to ask a question. the judge didn't stop, the broadcast inside, controlled by the inquiry, did. shouts of frustration from those in the room. well, some of the survivors who were inside are very disappointed with what they heard, and particularly with what they didn't hear.

some of the survivors saying that they're not sure they can work with the inquiry. six members of nabil choucair‘s family died in the fire. he just walked out. it was very disgusting and disappointing. very disrespectful. you would have liked him to have listened to the victims‘ questions? of course, he owes it to us. adel chaoui lost four relatives in the fire. we'd also like to reiterate concerns about the absence of a panel, which is the most important issue for bereaved families and residents alike. finally, the conduct of the chair at the end of the meeting, not addressing our concerns, is deeply distressing and disappointing. karim mussilhy‘s uncle died at grenfell. no, naturally, myself and members of the community, survivors, are not confident in the inquiry, but we're being optimistic and we're trying to keep an open mind, but we're here to make sure that the right questions are being asked. for ahmed, his optimism from this morning has gone. i am disappointed, because we went to the inquiry hoping that it's

going to ease us a bit, but in fact itjust makes us angry. but you're not going to withdraw your support for the inquiry? no, no, no. we're not. we're not going to withdraw it, we're going to carry on. the inquiry promises answers, but there's so much those who lost relatives and homes at grenfell still want and need to know. interest rates may rise in the coming months, for the first time in more than a decade. that's the warning from the bank of england. it voted to keep rates on hold at 0.25%. but the suggestion that interest rates may go up sooner than expected led to a sharp rise in the pound. 0ur economics correspondent andy verity reports. a new banknote with a famous writer on it. the hands of time are frozen as big ben gets a wash. not this year, but 2007, the last time interest rates rose. today, exactly ten years after worried northern rock savers

queued to take their money out of the failing bank, we heard hints that interest rates may at last be about to rise. in order to keep inflation, or return inflation to that 2% target, in a sustainabable manner, there may need to be some adjustment of interest rates in the coming months. now, we'll take that decision based on the data but, yes, that possibility has definitely increased. after the banking crisis struck, the bank of england slashed the official interest rate to 0.5%, the lowest it had got in 300 years, an emergency measure. since then, interest rate setters have met 97 times each time the question, when will rates rise? but each time they've done nothing, until last august, when they decided, in the wake of the brexit vote, to cut interest rates to a 0.25%. now the city thinks they'll go back up to 0.5% by december. a rise in the interest rate would help us greatly,

thank you very much, because we don't have mortgages. if you've got savings, you want to see them maximise out and give you a good return, but for years obviously that's not happened. well, in some cases, you want it to go up, because of your savings, but then in other cases you don't, because we've still got a mortgage. so we don't want it to go up for that. after the bank of england's warning, the pound jumped to more than $1.34, the highest it's been for a year. if the bank of england's signalling that it could be raising interest rates in the autumn of this year, thatjust makes the pound a more attractive currency for investors to invest in. it raises its value relative to other currencies. the higher pound won't help exporters, because foreign customers may have to pay more for their goods, but it should also mean imports are a little cheaper, slowing down price rises in the shops. executives at the security firm gas say they are ashamed by footage showing staff abusing detainees at one of their immigration detention centres. they were giving evidence to mps — following an undercover investigation by the bbc‘s panorama programme —

at a centre near gatwick airport. 0ur social affairs correspondent alison holt reports. it took an undercover panorama investigation to expose the realities of life at brook house immigration removal centre, near gatwick airport. run by gas, it's plagued by drugs and self—harm. with some officers reacting to detainees with bullying, abuse, even violence. failings which, today, jerry petherick, who runs the company's detention services, and gas uk boss, peter neden, had to account for to mps. i was ashamed of what i saw and i'm very sorry for what we saw. i can assure you that if we were in any way aware of any of that behaviour, we would have taken action. but former gas senior

manager nathan ward, now a priest, told the committee how he raised issues about bullying before leaving. he also described the intimidation he'd faced since speaking out. i've had my car tyres slashed four times, i've had four anonymous letters and, in the last week, received 12 anonymous phone calls. it's the home office that pays for services at brook house and next door tinsley house immigration removal centre. nathan ward told mps that financial and other information supplied to government officials about the places was not always complete. i'm also aware of inaccurate staffing reported to the home office, and that's part of the concern that i raised tojerry petherick on my resignation, and other financial matters like that. so do you think it's plausible then that gas has been, or people working at gas, have deliberately been giving false information to the home office?

categorically, yes. following documents shown by bbc news last night, which suggests significant profits of arund 20% or more on the two immigration centres in 2013, mps pressed gas bosses on the money they were making. we don't make profit of over 20%, that is overstated. do you make profits between 10% and 20%? i'm afraid, i'm just not at liberty to disclose the profits that we make. there's now been very serious evidence around abuse and mismanagement taking place. it means that i think, actually, it's not acceptable for you to simply provide no information about the profitability on these contracts. well, we do provide that information and we provide it to the home office, who is our client. gas says 11 staff and former staff have been suspended after the panorama. it also insists the information it provides the home office with is accurate. but, inevitably, this session will raise questions for the government about the monitoring of immigration detention services. a record number of people were detained by police in the past

year on suspicion of terrorism—related offences in england, wales and scotland. home office figures show there were 379 arrests, including dozens in the wake of the terror attacks in london and manchester. that's all from me. now, it's time for newsnight, with emily maitlis. do virtual currencies have a future or is a financial catastrophe just waiting to happen? as china bans bitcoin and one of the world's biggest banks condemns cryptocurrency as a fraud, we will ask an investor and sceptic if virtual currency is a bubble about to burst. gabriel gatehouse takes a trip to the dmz — the thin strip of demilitarised land separating north and south korea. we're in north korea now. north, south, north, south.

silence in memory of the victims of grenfell on the first day of the public inquiry. the chairman says he can and will get answers. we'll speak to the local mp who's concerned he wont succeed. the winner of the 2017 hyundai mercury prize is... ..sampha! and they've just announced the winner of this year's big mercury music prize. our very own steve smith's down there and hoping to have a word. cheering good evening. are we about to witness the collapse of bitcoin — the currency they told us could offer a safer, more secure option for trading? it was the libertarians' dream to kindle something that operated beyond governments, beyond institutions. but this week, one of the biggest banks in the world labelled bitcoin