A church in south London says it is saving people from a life of crime by using former gang members to show others a different way of life. How does it work?
It is not a scene you would expect to find in a church.
Lead pastor Tobi Adegboyega asks members of the congregation to make their way to the front with any weapons they may have in their pockets.
It is a system based on trust but such amnesties have proved successful.
"We've had times where people are coming to the altar and dropping their knives and drugs," explains fellow minister Connor Callaghan.
"Last week I was praying for a 23-year-old who was recently released from prison and he was crying."
This is Spac Nation Ministries, a "young dynamic church" in Southwark.
Its preaching is tailored to a different kind of congregation - former armed robbers, drug dealers, gang members and one man who spent time in prison for attempted murder.
By its own figures, 55% of those that attend have previously been involved in a life of crime.
Connor himself has served time in prison.
"I went to jail for some robberies, possession of a bladed article. I was charged with money laundering of £30,000.
"But I feel like if I had come here before, I would have been shown the right mentorship and guidance."
Connor says he has turned his back on his former way of life, something the church hopes to replicate with others.
Lead pastor Tobi says his success in helping to reform ex-criminals lies in his ability to connect with them and offer them a level of support the official routes cannot.
He currently has 14 ex-criminals living in his house, and has been known to pick people up from the prison gates to ensure they do not fall back into trouble.
He also takes a different approach to many ministers in the way he dresses, wearing ripped jeans while preaching - something he jokes he never would have previously envisaged.
"I understand our approach is different from a traditional church. I've got to look like them [the congregation]. I've got to connect with them.
"I've got access and I'm speaking to the worst of the worst - people who have done the most despicable things. And I sit down with them and we talk."
It is an approach approved by the authorities, given that Tobi's position allows him to build a level of trust with people who may not have the same faith in the police.
Chief Supt Sean Yates, who heads up the Metropolitan Police's knife crime unit, told the BBC he wanted churches "to be seen as safe spaces for young people, places they can go and talk to someone".
The force says it is "committed to targeting knife crime through enforcement and education, but... we need the help of the community to tackle what is a very complex issue".
Spac Nation's methods, however, are not without their critics.
The church has been described as a "cult", its pastors do not have to undergo formal training and members are encouraged to flaunt their wealth in order to make the church look glamorous to the gang members it wants to attract.
But Tobi rejects such criticism: "I show them what they've always wanted to be, and that they were looking for it in the wrong place."
One of the ways the church does this is to actively take to the streets and seek out gang members it believes it can show a new way of life.
Ex-gang members who are respected in such circles lead the way.
In Croydon, south London, preacher David Adjaye - a former leader of DSN, one of Croydon's largest criminal gangs - is keen to pray with people on the streets.
London has just had its worst year for knife crime for some time, with 26 teenagers stabbed to death.
"We don't care who we approach," says David. "We're coming as peacemakers to offer these people help.
"It is a dangerous thing to do but with a good heart we know all is well."
Having been in a similar situation to those he talks to, he hopes his experience gives him the trust and authority that others in the community may not have.
Minister Daniel Ogoloma explains: "An elderly person who has never been on the streets of Brixton can't tell a gang leader why they can't carry a knife.
"What the [gang member] needs is to build partnerships with community leaders who have been in that position."
It is an ethos that is at the heart of the church.
"If knives and guns take human lives, it is the role of the church to save lives," says Tobi.
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