Police have warned a "malicious campaign of intimidation" by animal rights extremists against individuals who may be involved in medical research may be coming to Cumbria.

Anonymous letters sent by the extremists have accused the recipients in other parts of the country of criminal sexual offences.

Police spokesman Mike Head said similar letters could be sent to medical researchers in this county.

Assistant Chief Constable Graham Sutherland said: "If any member of the public in Cumbria receives a letter of this nature, they can be assured the allegations are completely false."

"If anyone receives such a letter, I would urge them to report it to the police," he said.