Tough sentences to cut knife crime are given to too few, campaigners claim.

Figures showed that despite new laws to give people who carry a blade up to four years in jail, only two out of more than 6,000 sentences were given the maximum penalty.

The news comes just a week after two teens were rushed to hospital after a stabbing in Lambeth.

Lyn Costello, of mothers against murder and aggression told the News of the World it made "a mockery" of the law.

The figures from 2006, released by the Ministry of Justice, showed that of the 6,284 sentences for carrying a knife in public, almost 3,000 were given community work.

And the Independent on Sunday revealed last week that the number of under 18s convicted of carrying a knife more than doubled from 482 in 1997 to 1,256 in 2006.

The startling statistics come as Jacqui Smith prepared to unveil her £1million Tackling Violence Action Plan tomorrow.

The plan includes giving the police hundreds of metal detectors to be used at pubs and clubs to catch young people carrying in hidden weapons.

The Home Secretary also wants to allow schools and colleges to search all pupils under suspicion of carrying a knife as part of the conditions of their enrolment.

It is one of a number of measures to shift responsibility to parents, who would have to sign up to much harsher scanning and searching policies for their children.