POLICE are warning pensioners to be on their guard following reports of a gang operating as bogus knife sharpeners.

But they say they are making progress in tackling the problem of bogus callers after two men were arrested for house burglaries in north-west Durham.

The knife sharpening con follows dozens of similar incidents that have involved bogus water, gas and other officials.

Those involved are thought to be members of a large gang, including at least one woman, who walk uninvited into old people's homes. They either sharpen knives and charge exorbitant fees or use the opportunity to steal from their victims.

The gang is thought to be responsible for dozens of crimes since last autumn, and detectives believe many more have not been reported because victims are either not aware that they have been conned or are too embarrassed to call the police.

Det Insp Neil Redhead, of Durham Constabulary, is co-ordinating inquiries into the gang's activities. He urged pensioners to be vigilant in keeping their homes secure.

He said: "These criminals are absolutely despicable. We are very concerned, because they are preying on the elderly as they are easy pickings.

"They have been active just about everywhere in County Durham and also in neighbouring areas. All the forces involved are pooling information and doing their utmost to catch these individuals.

"In the meantime, our advice to vulnerable people is to get a security chain fitted and not to let in any uninvited callers you do not recognise."

News of the bogus knife sharpeners comes after 50 sneak-in burglaries were reported in South Stanley and South Moor in three months.

Det Insp Redhead said it was vital that people contacted the police if they were targeted.

"If you have any doubts or fears, contact your warden, if you have one, or the police. Nobody minds being called out for what may be a false alarm," he said.

* Two men, aged 35 and 49, have been charged with burglaries at homes in the Consett and Stanley areas. They will appear before Peterlee magistrates on May 31.