Scenes-of-crime officers are heading for a £1 million overspend but there are no gloomy faces at Sussex Police.

The force is reaping success from spending more money on DNA profiling from crime scenes and suspects.

It is expecting a record 900 successful DNA "hits" this year compared to less than 200 in 1997-98.

Sussex Police hope to trim the overspend with the help of Home Office money and tighter housekeeping.

Part of the overspend is due to DNA testing on people involved in "cold cases", including unsolved murders, some dating back more than 30 years.

Brian Cook, the force's scientific support manager, said there had also been a heavy spate of major crime this year that required expensive work by scenes-of-crime officers.

A DNA test sent to the Government's Forensic Science Service laboratory at Lambeth, London, costs £250 but "fast-track" tests for urgent cases are another £2,500.

He said the force would recover money from a penny-for-penny Home Office grant system for DNA testing.

There will be no cutbacks on DNA testing but officers have been asked to tighten up on other work.

Mr Cook said: "We have asked them to give a lot of thought to items they are sending for other tests to make sure what they are sending is likely to be useful."