TEN shops have been caught illegally selling knives to teenagers.

The Greenwich borough stores were found selling blades including craft, kitchen and steak knives, to undercover police cadets as young as 14.

Despite public concern about increasing youth violence, 10 out of the 27 shops visited sold the potential weapons to the teenagers.

They included two branches of Sainsbury's and the Eltham High Street branch of Woolworths.

Under UK law, people need to be aged over 18 to buy a knife.

The operation was carried out by Greenwich Council trading standards officers, the Met and safer neighbourhood teams from September 6 to September 20.

Each shop has now been sent a letter of caution and could be prosecuted if they fail another test purchase.

Greenwich Council cabinet member for neighbourhood services Councillor Maureen O'Mara said: "It's appalling that so many stores appear to be flouting the law with underage sales - especially when selling knives to children."

A spokesman for Woolworths said: "We are aware of the incident in Eltham and have conducted a thorough investigation as a result. The stores are reinforcing our policy on age-restricted sales to all staff. "

And a spokesman for Sainsbury's said: "Sainsbury's has launched a full investigation into how this took place."

The 10 shops:

Avery Truman, Eltham High Street Woolworths, Eltham High Street Pound Stop, Pound Place, Eltham B&Q, Bugsby's Way, Greenwich Sainsbury's, Bugsby's Way, Greenwich Poundland, Powis Street, Woolwich Sainsbury's, Woolwich High Street CK Builders Merchants, Herbert Road, Plumstead LouRoys, Herbert Road, Plumstead Pound Shop, Plumstead High Street