A group of young people at a New York City jail complex got some words of encouragement from hip-hop mogul Russell Simmons and actor and musician LL Cool J.

The pair visited Riker's Island's juvenile detention centre to mark the launch of a national anti-violence programme from Def Jam co-founder Russell's RushCard, a pre-paid debit card.

RushCard's Keep the Peace initiative is giving grants to neighbourhood organisations. One of those is LIFE Camp, a Queens organisation that works with young people, including those at Rikers, to reduce violence.

LL told the audience that his rough upbringing could have had him where they were if things had worked out differently and encouraged them to believe in themselves.

"You can absolutely without a doubt do anything you put your mind to," he said.

Russell told them to focus on what was inside them. "It's your spirit you've got to work on," he said.

Deputy warden Clement Glenn said partnering with programmes like LIFE Camp is among the ways the Department of Correction tries to get young people to change their behaviour.

We're "trying to encourage them not to come back into the system, hoping they will integrate into society and become contributing members of their community," he said.