THE telephone - it looks harmless enough but misuse it and you could face a manslaughter charge.

An elderly woman in County Durham, who police believe was the victim of a nuisance caller, collapsed and died of a heart attack minutes after a receiving threatening call.

Police are treating the phone used by the anonymous caller as a deadly weapon and have launched a manslaughter hunt.

The story may be an extreme case of the problem which plagues more than 500 people in the North West every week - but similarly shocking incidents are all in a day's work for telephone troubleshooters at the region's malicious calls bureau. The 25-strong team of specially-trained investigators at the Blackburn-based bureau are on hand to help the victims of all unwanted phone calls, from silent ones through to those involving threats and abuse. Our message to the public is if you need us we are here," said Christine, an experienced operator from Great Harwood.

She has been trained to give help and advice to victims, setting up traces to pinpoint the culprits behind the crime and putting together a package of evidence for the police.

"It can be distressing for the recipient of these calls," she said.

"My job is to put the victim at ease and tell them about their options." Colin, who has been at the unit for three years, added: "It is a very rewarding job.

"We do everything in our power to identify offenders and it is gratifying to think we have helped to end calls to vulnerable people or hoax calls to the 999 service."

To speak to an operator, ring free of charge on 0800 661441 during office hours.

BT also provides a free 24-hour recorded information service on 0800 666700. HERE is a breakdown of a typical malicious calls investigation, based on the experience of a Blackburn woman:

Complaint made to the police about a spate of vile and abusive messages.

Police request malicious calls unit to set up a trace on line. This is done within seconds.

Woman contacted at regular intervals and asked to keep a log of offensive calls.

Caller is traced.

Information about the origins of calls sent to police.

Officer visits the suspect and told if calls continue further action will be taken.

Calls stop and victim and police decide to leave the matter there.

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