THE calls would come in the early hours, 10 to 15 at a time for several nights running. It got so bad that Alexandra Eddy feared the trill of the phone as much as the obscenities she would get when she answered.

Even now, with her tormenter exposed and off-line, she still feels that sickening sensation. It will be some time before the phone can be a normal part of her life again.

Alexandra, a mother of two young daughters, was one of the Herefordshire women that serial sex pest Roger Lacy rang at random. The calls came in from a mobile over the early hours, one after another, and if a woman answered, Lacy would start his obscene tirades.

Between 10-15 calls a night would come Alexandra's way, up to four nights at a time for several weeks running.

"It was horrifying. I didn't know if he knew where I lived or if he was watching me," said Alexandra.

As the calls continued and worry took over her life, Alexandra went to the police.

Officers quickly linked her complaint to several months worth of similar reports from the Hereford area about obscene calls in the early hours randomly received from withheld mobile numbers.

What was said, and the way the caller said it, showed a serial pattern and the officers were sure they were dealing with same suspect.

The findings went to the specialist BT nuisance call team and a tracing operation was set up. The details of such operations are highly technical and have become more so as mobile phone use advances.

All Alexandra had to do was tap in a special four digit code straight after she took an obscene call. That opened up an electronic trace allowing the BT investigators see what number the call had come from.

The paper and data trail that all mobiles can leave - even pre-paid models - led them to Lacy, who lived at Shifnal, Shropshire.

Lacy, aged 49, admitted a series of offences against the communications act when he appeared before Hereford Magistrates last week. He was given three years of community supervision and ordered to complete a sex offender course.

The court heard that Lacy was ashamed of his actions and was getting counselling.

Though it's been months since the calls stopped, Alexandra says she's still sent into a panic whenever the phone goes, especially at night. But in speaking out, she is taking back some control and setting an example for her two girls.

"They can see no woman has to put up with these calls and that something will be done when they happen," said Alexandra.