DNA samples taken from car thieves are being stored on a database as part of a crackdown on car crime.

People charged with breaking into or stealing vehicles have a mouth swab taken at a police station and, if they are convicted, their unique DNA "fingerprint" is stored on computer.

If suspects are acquitted or the charges dropped, the samples are destroyed and not recorded.

Samples are already taken in burglary and assault cases but now Home Office funding means car crime can be included.

Detectives are also working more closely with scenes-of-crime and forensic officers in collecting DNA samples, as well as other evidence such as fingerprints, from cars that have been broken into or from recovered stolen vehicles.

Detective Sergeant Jim Elston, of Eastern division, which covers Blackburn and Hyndburn, said: "Legislation has been in place for several years that allows the police to take a swab of saliva for recordable crimes. In the past the decision was taken to do that for certain offences, such as burglary and sexual offences, to avoid a log-jam for forensic experts.

"Those strict parameters have now been removed to include other offences such as car crime."

Sergeant Jim Masterman, of the Pennine division, which covers Burnley, Pendle and Rossendale, said: "The police have had some startling successes nationally through DNA. I can see the day will come when all crimes will be covered."

A national "Crime, let's bring it down" advertising campaign, the first for four years, aimed at cutting car crime nationally by 30 per cent by 2004 was launched.

With the message "don't give them an easy ride", the campaign gives practical advice to drivers -- park in safe areas, activate an alarm or immobiliser, shut windows and lock doors, and don't leave anything on display.

Home Secretary and Blackburn MP Jack Straw said: "This campaign is about the simple actions motorists and their passengers can take to outsmart the thief."