London: Mayor Boris Johnson's deputy announced on Tuesday plans to step up the fight against gangs in a bid to halt the spate of teenage murders on London's streets.

Deputy mayor for policing Kit Malthouse said it was time for communities to say "no more" to the trouble caused by groups of violent youths.

He said young people were a key part of the solution and they should start by reclaiming the word "gang" from its negative associations. Instead of trying to prevent teenagers from forming groups the authorities should focus on diverting the energy of gangs to more fruitful ends, he said.

The Metropolitan Police will set up an operation designed to pull together all its previous work on tackling gangs. At the same time City Hall will focus just as strongly on "longer term, more complex" work to change gang culture.

It comes after 19-year-old Oliver Kingonzila was knifed to death during a fight outside a Croydon nightclub on Saturday, the 26th victim of teenage violence this year.

Malthouse, addressing a peace conference at City Hall, said: "We will be stepping up our efforts to combat gangs in London. Much of the violence we see on our streets today is caused by these gangs and it is time we confronted them as a community. It has to stop. It cannot go on. The Mayor and I refuse to believe nothing can be done."

He added: "Young people are part of the solution to the problem. Perhaps the word 'gang' needs to be redeemed and the challenge that we face is not one of preventing young people from forming and belonging to groups we call gangs, it is to create the environment that helps them to use their individual and group strength...for positive peaceful ends."