Youths had to face the decisions anti-terror police make in an instant
On the fifth floor of Scotland Yard in central London, live video feeds are coming in with news of a terror threat.
The 30 people in the room are forced to make decisions that could change lives - which homes do they raid? Who do they stop and search?
But they are not counter-terror officers - in fact, many of them are not even sure they trust the police.
They are 17- to 25-year-olds from around London, nearly all of them Muslim, and they are acting as if they are officers responding to a terror attack as part of Act Now, an exercise run as part of the government's £140m Prevent programme.
It aims to stop young people feeling isolated or having mistrust for authorities - targeting those that the government and the police agree are vulnerable to radicalisation.
Ali Al-Musawy, 17, is from Kenton, west London. He spent his early teenage years causing trouble for the police and his family.
There are youths that say 'why's he coming to me on suspicion of terrorism, do I look like a terrorist?'
He has turned things around but still has gripes with the police and, like all the youths in this room, his main problem is with the police's stop and search powers.
"That is a big issue, because there are youths that say 'Why's he coming to me on suspicion of terrorism, do I look like a terrorist?' and 'Why can't they search the other white guys, why can't they be the terrorist?'
"That's an issue with the police, they should know how to handle things."
Hanad Mahamood, 24, is a youth worker from Brent in London and he holds the view of the police that the exercise is designed to change.
"I was being stopped and searched just for being a black youth and Islam is on the agenda now.
"I feel even more victimised by the police now and I know most people in my community do."
Police hope the Prevent exercise will give young people a better understanding of why and how the police make decisions, fostering better community relations.
Shaheen Qadir and Hanad Mohamoud on whether Act Now works
The scheme funds projects across England and Wales, including boxing clubs and internet lessons for Muslim mothers. Three hundred new officers are currently being recruited to carry out more of the work.
Plenty of the young people have hailed Act Now, which began in Lancashire, as a success.
Ali is one of them. "The bottom line is to kind of work with the police to try to resolve these issues, these problems, the bombings that happen, working with the community and the police and making you realise that the police ain't always there to pick on you or hate you."
I have friends who have controversial views, basically I know they wouldn't be caught dead at these kinds of events
But Hanad said he did not believe the course was the answer to dealing with the threat of terror attacks and labelled it a public relations exercise.
"I feel it was a case of 'You need to understand that these are all the problems that we (the police) go through.'
"I really didn't care all the problems the police go through because they get paid to go through those problems.
"I have friends who have controversial views, basically I know they wouldn't be caught dead at these kinds of events, it's kind of working with the enemy, so what's the point if you're just preaching to the choir?
"As a tool for anti-terrorism I think it's a waste of time."
The Metropolitan Police stressed the point during the exercise that Prevent was not just targeting Islamic extremism but was also focused on animal rights and far-right extremism.
But the Prevent agenda has been criticised for its impact on Muslims.
Some community leaders told BBC Asian Network they were going to stop taking Prevent money because they felt it had had a negative impact.
Others said they felt it labelled all Muslims as potential extremists and that was making community relations more difficult.
Some moved away from the programme after the Met said they wanted youth leaders and community groups to pass information on to anyone who appeared vulnerable to radicalisation.
Community worker Mohammed Azam, from Ilford, Essex, had used Prevent money in the past but said he would not in future.
What we're looking at is to identify vulnerable individuals and I think that's something that the police and other partners have been doing for a number of years
Supt Mark Goldby
"Some of the people doing this (community) work, they've been doing this for years now and it's not possible that their good name be tainted even with the possibility that they're working with the security services or informing on people."
He argued that passing on information was not part of the arrangement when he began taking Prevent funding.
"Self-respect and dignity is worth more than that and we're not going to do it for the money," he said.
The Met's Supt Mark Goldby, who is leading Prevent, said it was not about spying on people, just identifying those who were at risk.
He said: "What we're looking at is to identify vulnerable individuals and I think that's something that the police and other partners have been doing for a number of years as far as crime and disorder is concerned.
"Prevent is a different ballgame, but nonetheless it's about identifying who's vulnerable, who does need that support and where can we provide the resource and the support to help the individuals."
The minister responsible for Prevent, the Policing and Counter-Terrorism Minister, David Hanson, said youth workers had a duty to others to inform police of suspicious behaviour.
"I would expect and I would understand that youth workers who have real concerns should share that information in a broad sense.
"I think that's perfectly legitimate, if somebody is at risk of causing a risk to not just themselves but to the community at large."
Listen to a series of reports about Prevent on Asian Networkat 1230 and 1800 GMT on Monday, Tuesday and Wednesday or online via theBBC iplayer.
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