ELDERLY people in Epping Forest have been warned to stay on their guard after a string of thefts by conmen pretending to be police officers.

More than £34,000 has been stolen from pensioners this month alone, with dozens of people being targeted by the men across the county.

The conmen operate by posing as Metropolitan Police officers who claim to be investigating bank account fraud.

They then ask for a PIN number over the telephone, and tell their victims that bank cards should be left in an envelope outside the frontdoor or halfway through a letterbox so that they can be collected later.

The cards are then picked up and then used to withdraw large sums of cash.

One recent incident saw a pensioner in Braintree tricked out of £800, and police fear the conmen could strike in the Epping Forest district.

A police spokesman said there had also been attempted cons in in Chelmsford, Wickford, Braintree, Billericay, Brentwood, South Ockendon and Dunmow.

He added: "In some cases victims are phoned regularly, sometimes hourly, throughout the day as the fake officers try to convince people to follow their instructions.

"Some people who have refused to carry out the instructions have been subjected to abuse and even threats of violence."

Chris Willis, a Territorial Policing inspector based at Essex Police Headquarters, said: “We all need to work together to combat these despicable people who are preying on the more vulnerable and also genuine and trusting members of our communities.

“A legitimate person would never, under any circumstances, ask you to disclose your PIN number for a bank card over the phone, and anyone receiving such a request should terminate the call and consider calling the police. In addition, no-one would ever legitimately ask you to hand over your bank cards.

“We can all play a part in stopping these appalling offences and Essex Police encourages people to speak to neighbours, friends or relatives, making sure they understand the good advice given above. The more people who are aware of this type of crimes, the less chance there will be that these wicked people will be successful.”

Anyone who is contacted by the tricksters should contact police immediately on 0300 333 4444.