A HORRIFYINGLY brutal sex attack on a woman walking her dog in a popular East Lancashire beauty spot almost ten years ago is probably the area's worst unsolved crime. Scores of men have been DNA tested and eliminated. Tonight, Crime Reporter IAN SINGLETON looks at how new DNA advances mean police are confident they are closing in -- and will eventually catch the rapist. . .

ADVANCES in the use of DNA have given police renewed hope of snaring a notorious East Lancashire rapist they have been trying to track down for nine years.

"If this man is still alive, we will eventually catch him," said the officer who led the hunt for the attacker who struck in Billinge Woods, Blackburn, almost a decade ago.

Up to 100 men, who match the offender's profile, have voluntarily given their DNA, revealed Superintendent Neil Smith.

This is on top of DNA checks against the national database by forces across the country when arrested people's samples are added to the system.

The news came as police in London, investigating the murder of Rachel Nickell on Wimbledon Common 12 years ago, found a DNA match to a sex attacker after using new technology to find a minute sample from her clothing.

And police in Lancashire are hopeful technological advances can also point them in the direction of the sex attacker.

The rape in Billinge Woods, in October 1995, was described by detectives at the time as the worst of its kind ever in Lancashire.

A 22-year-old woman, who was walking her dog, was bound and dragged into woodland before being subjected to an hour-and-a-half of rape and sexual assaults.

An appeal for information has twice been run on BBC1's Crimewatch, and five chilling letters believed to be from the rapist were sent to police between 1995 and 1998. But the attacker has remained at large.

Around 800 DNA tests were carried out on men until the inquiry was scaled down in 1998 -- yet police have never stopped hunting the attacker. Officers are constantly on the lookout for men who match the profile of the rapist.

As a result, as many as 100 have voluntarily given their DNA since 1998 -- even though they may not have been arrested.

The ongoing hunt for the rapist came to light after it was revealed that a man who downloaded 800 images of child porn from the internet was also asked to give a sample.

The man was eliminated after his DNA was analysed this summer. He was jailed for a year last Friday after pleading guilty to eight charges of downloading, or possessing, the images.

Supt Smith, who led the investigation, said: "We pro-actively take DNA from people who come into our radar. We have asked everybody who might fit the profile of the offender to submit their DNA for comparison.

"These are people who might not specifically get arrested by the police, but are brought in because of what someone has told us.

"Advances in DNA and increased technology have given us much better chances of identifying this person."

DNA is estimated to be a major factor in solving around 1,100 crimes every year in Lancashire. More than 12,000 samples are taken from prisoners to store on the database.

DNA testing has quadrupled since 2000 when the government started short-term funding to encourage forces to use new technology.

Since then, one million samples have been added to the national DNA database. This process is now fully automated, which allows 40,000 samples to be uploaded every month.

As of this April, police forces were given the power to take, without consent, a DNA sample of a person arrested for an offence which they think is likely to result in a prison sentence.

Previously, they were not allowed to take a swab until a person was charged.