Shop workers in Burnley, Hyndburn, Pendle and Rossendale were found to have sold knives to under 18-year-olds, police said.

On Monday officers conducted a knife test purchasing operation as part of Operation Sceptre.

During the operation police visited 12 shops, of which three failed the test and sold items to children under the age of 18.

PC Nathan Shaw, from Hyndburn Police, said: “Knives are dangerous and the sale of them to children is not only illegal but puts them at risk too.

“We will continue to take action and carry out operations like this one to ensure those selling these items do so legally.

"If you have any information on young people purchasing knives in local shops, please do contact us so that we can take appropriate action.”

As part of the work to support Operation Sceptre, officers will also be carrying out community engagement and educational school talks to raise awareness of the consequences of carrying a knife.