"We've lost a lot of young people around here," reflects Saleh Luqman, casting a coach's critical eye as a cluster of teenage boys conscientiously shoot basketballs into a net.
"In the last few months it's been under the radar and out of the headlines, but if you look inside the paper it's still going on, every week. There are a lot of vulnerable people out there."
For the youngsters, this Saturday morning session in a school gymnasium in the north London borough of Enfield is a chance to hone their crossovers and perfect their layups.
But Luqman, one of the growing number of black converts to Islam in the UK, is more concerned about the bigger picture. While the brutal death of British soldier Lee Rigby in London in May and the current trial of the two men accused of murdering him have made headlines around the world, young black males are the routine victims, and perpetrators, of extreme violence on the streets of the British capital.
In September, one expert on social exclusion compared the level of violent crime in some London neighbourhoods to the favelas of Rio de Janeiro and warned that some children in deprived communities were "growing up in a culture of 'easy dying' in which human life is not valued".
"The police call it gangs," says Luqman, whose work is backed by the Salam Project, a community organisation that aims to challenge negative stereotypes of black and Muslim youth and address issues such as gun crime, drug dealing and extremism.
|Inside Story - Woolwich attack: an act of terrorism?
"But that's already putting young people at a disadvantage, and some of them buy into it. Since 9/11 people have been looking for terrorists and extremists, but all we want is to do the best we can in this country where we live and do the things that are honourable and good. I just try to show them how I live my life as a Muslim."
Islam is quickly emerging as the religion of choice for young black people, many raised as Christians, in the UK. About 270,000 people in England and Wales (14.5 percent of the black population), identified themselves as black Muslims in the 2011 census, compared with just 106,000 (nine percent) a decade earlier.
But that trend has become a cause for concern among some community leaders who see the embrace of Islam as partly symptomatic of a widespread rejection of a society, in which many black people continue to experience discrimination and marginalisation on a daily basis, and in which young black men are being criminalised and jailed in ever greater numbers.
Figures published last month by the Ministry of Justice showed that black youths were six times more likely than white youths to be stopped and searched by police. If convicted, they were 20 percent more likely to be sent to prison and would typically serve a sentence seven months longer than the equivalent punishment for a white offender.
Michael Adebolajo, one of the two defendants currently standing trial over Lee Rigby's death, last week told the court how he had been raised as a Christian but became a "soldier of Allah".
"My parents used to take us to church every Sunday. The memory that sticks in my mind... is probably every New Year's Eve in the evening around 11 o'clock we would gather around in candlelight and read passages from the Bible," he said. Adebolajo admitted killing Rigby, but he and co-defendant Michael Adebowale deny murder charges.
Lee Jasper, a race relations activist and one-time adviser to former London mayor Ken Livingstone, sees worrying parallels between the shocking violence in Woolwich and the situation in south London a decade ago, when saw disaffected and demonised gangs of black youths targeted and converted by extremists, and in turn converting rival gang members at gunpoint. He believes the conversion rate among young black men in prisons also remains concerning.
You often find that converts are the most idealistic and the most hardline activists.
"Black rage against institutional racism has massively increased and it provides a willing group of vulnerable young people who are susceptible to this kind of radical Islam," Jasper told Al Jazeera. "We are building up a pool of really pissed-off angry young men and I'm worried that we are not alive to the problem."
Jasper's concerns are echoed by experts on radicalisation who say extremist preachers will often court support among converts, who typically lack grounding in mainstream Muslim culture.
"You often find that converts are the most idealistic and the most hardline activists," Nick Lowles, co-ordinator of the anti-extremism campaign group Hope Not Hate, told Al Jazeera. "They haven't got the family networks. They haven't experienced other ideas or traditions within Islam. Their only interface with Islam is via these extremists and that extremism becomes the norm."
One convert, who did not want to give his name, told Al Jazeera, "A lot of converts come to Islam because we see it as a solution to problems that normal society doesn't have the answers for. So once we accept Islam we are more hardcore in it."
Influx of converts
In Brixton, the historic heart of south London's African-Caribbean community, AbdulHaq Ashanti, a spokesman for the local mosque, explained to Al Jazeera how Muslim leaders there had been fighting radicalism since the 1990s. Once synonymous with Rastafarianism and a permissive ganja-and-reggae-infused counter-culture, Brixton, Ashanti said , had seen an influx of young black converts adhering to the mosque's strict Salafist interpretation of Islam, with "massive growth" in the Muslim population since 2004.
But the mosque has been forced to confront radicalisation in its midst since 2001 when Richard Reid, the so-called "Shoe Bomber" who attempted to blow up a transatlantic flight, and Zacarias Moussaoui, a Frenchman convicted in the US over the 9/11 attacks, were revealed to have passed through its doors.
Both Reid and Moussaoui were alleged to have subsequently become acolytes of Abu Hamza, a jihad-preaching cleric based in north London who was extradited to the US in 2012 to face terrorism charges. Another extremist figure, Abdullah el-Faisal, a Jamaican-born convert, was expelled by Brixton Mosque in 1993 and eventually banned from the UK in 2007. "We have had to deal with this head-on," said Ashanti. "We've had these people coming in and we've had to keep ourselves on our toes in terms of the arguments they use."
The mosque has a track record of working with young converts and former convicts, and Ashanti said there were many positive stories of men with troubled histories who had found the strength through Islam to straighten out their lives. "There is a strong emphasis on community and there is a support structure for them," he said. "We have people who have come out of prison and taken the time to sort themselves out, gotten married, had kids, and now they're working and doing very well for themselves. People will always trace that back to when they became a Muslim. But you won't see those stories in the papers."
But Ashanti said cuts to funding for counter-extremism programmes, and a reorientation of policy under the UK's right-wing coalition to put distance between the government and more fundamentalist organisations, had made it harder to reach out to those at risk. Victims of the cuts since 2001 have included local youth projects and a mentoring scheme for Muslim prisoners. "If someone goes into prison now or someone is vulnerable in prison based on information that comes to us from the community, then there is nothing we can do because we can't get back into the prisons," said Ashanti.
For now, Saleh Luqman's basketball sessions have survived. But he admits he has already been forced to move to the cheapest gymnasium in the area as funding for engagement work has dried up.
And he fears that one consequence of Woolwich, amid greater scrutiny of mosques and Islamic organisations, could be that many wayward individuals vulnerable to radicalisation or criminalisation are abandoned out of fear of the bad publicity their future actions could bring.
"We are extending arms everywhere to be part and parcel of everyday life," he says. "Our mission is community cohesion and we intend to achieve it, not for the stats or anything like that but because it is our life - and that's it."
Follow Simon Hooper on Twitter @simonhooper