It was both a prayer vigil and a protest. As the police launched a fresh appeal for witnesses to the murder of Michael Dosunmu, the Peckham teenager shot in his bed this month, hundreds gathered in a square close to his house and pledged to fight gun crime.

Lucy Cope, an antiguns activist who lives in the neighbourhood, said that the feeling in the community was “one of absolute horror”. “I’m surprised no one has been charged yet,” she told The Times. “There certainly has not been a wall of silence.”

She feared that there could still be reprisals. “Whoever the perpetrators are, they won’t be acting normally. Their mothers or their girlfriends will know. These people need to come forward.”

At 5pm yesterday church leaders, antigun campaigners and hundreds of local people gathered outside Peckham library. They sang the spiritual anthem We Shall Overcome and the hymn Amazing Grace.

“I don’t think I need to make a speech,” said Home Office Minister Vernon Coker, addressing the gathering. “The speech was made with the singing that took place over there outside the library when the people of Peckham, the people of London, all of you stood and sang We Shall Overcome.”

There were cheers as Cressida Dick, the newly appointed Deputy Assistant Commissioner of the Metropolitan Police, told the crowd: “I assure you, we will do everything in our power to prevent guns coming into this community and we will do everything to bring to justice those who have committed such terrible crimes.”

She told the marchers: “We can fight violence in our communities, the police are standing alongside you, we recognise your courage and your determination . . . we want to work with you. The police alone can never solve a problem like the problem we face here.”

Then the crowd moved out of the square and marched west down the High Street, stopping on the corner of Southampton Way, where Javarie Crighton, 21, was stabbed to death this month. They observed a minute’s silence.

Isaac Attram, whose son Eugene was murdered in South London last year, spoke of the role of fathers in combating gun crime. “Make sure you are talking to your children and make sure you know where they are,” he said.

Listening in the crowd was Tony Thomas, whose son, Adrian was the ringleader of the gang that tortured and murdered the Reading teenager Mary-Ann Leneghan.

“I’m glad to be here and be part of what is going on,” he said. “My thoughts are with the families of those who have lost their children . . . Our community is being tarnished by the actions of a few.”

The march moved towards Brixton. “Parents have spoken to us about young people going to school wearing bulletproof vests,” said Pastor Les Isaac, director of a church organisation that sends volunteer pastors on to the streets at night to talk to young people.

“I’m walking because there is an expectation that the church should do something — stand with those who are mourning. They should also find a way forward to get our young people out of this quagmire.”

The march ended near the McDonald’s in Brixton, where two teenagers were shot last September.

Six men have been arrested in connection with the shooting of Michael Dosunmu. All have been bailed.

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