A TELEPHONE sex pest believed to be responsible for hundreds of perverted calls to teenagers, mostly in the Darlington area, has resurfaced after more than two years.

The man is thought to have been responsible for around 50 calls in 1998 alone, but his sporadic spates of telephoning youngsters is thought to go back some four years and this is thought to be "the tip of the iceberg".

Most times, the man has claimed to be carrying out a survey for a radio station - which police say does not exist - and asked to speak to a teenager in the home.

But, following a few general enquiries, police say the questioning quickly turns to a sexual nature.

The latest incident happened at around 3.30pm on Friday, when a 14-year-old boy in Darlington was the recipient of the call.

Although most of the calls were received in the town, police have linked the same man to incidents in 1998 in areas such as Trimdon, Spennymoor and Willington.

DC Peter Eddy, of Darlington police, said: "The questions very quickly turn into personal questions of a sexual nature."

And officers are urging anyone who receives a call to do a number of things:

* Immediately dial 1471 when the person hangs up to see if there is a number available.

* Make a note of any accent, background noises and the things that are said.

* If possible, hand the phone to an adult who should make an effort to get information out of the caller.

* Call PC John Milburn at Darlington police on (01325) 467681 to report the incident.

And Det Con Eddy also warned recipients of such calls never to give out personal or contact details of themselves or friends.

"If anyone does receive a call, if they can note what is said and details of any accent or background noise and not give any numbers of friends, then call us," he said.

The man does not ask for the teenager by name, but on one occasion in the past called the same house four or five times until the youngster he was looking for was home.