Retired detectives are to be enticed back to work in a bid to combat falling detection rates.

Up to 30 former officers, as well as experts in computer and finance crimes, are to be brought in by Sussex Police to beef up investigations.

They will help fill gaps created by a record number of detectives leaving the force to enjoy the extra £6,000 they can earn working in London.

Fifteen detectives, many with years of experience, left Sussex in the two months to mid January, the biggest brain drain in force history.

The loss of their expertise is seen as part of the reason detection rates have fallen.

Crime fell two per cent last year and overall detections in Sussex were slightly up by two per cent, one of the few increases recorded in England and Wales.

But there were falls in detections in key crime categories.

Latest figures show 93 out of every 100 car crimes remain unsolved.

Hiring former detectives, thought to be the first move of its kind in the South, is part of a package of measures that will cost the average taxpayer an extra 50p a week.

Most of the defecting detectives have taken new jobs with the Metropolitan Police where they earn more and enjoy free travel.

Assistant Chief Constable Tony Toynton agreed their departure was part of the reason for the dip in detections.

The force set a target of solving 18 per cent of all burglaries for the nine months to December but figures show they fell well short, with only 12.7 per cent solved.

Violent crime inquiries also suffered. Just over 58 per cent were detected compared with the target of 65 per cent.

Only seven per cent of all vehicle crimes were detected, short of the ten per cent target.

Mr Toynton said: "The rates were disappointing and not what they should be."

He said as many new recruits and transferees were joining Sussex as were leaving but time was needed for the newcomers to be trained up or get accustomed to their new duties and areas.

An advertising campaign has been launched to entice London police who live in Sussex to switch to the county force and avoid the drudge of commuting.

And in a move to help stem the drain, Chief Constable Ken Jones is close to signing a deal with bus and train operators to provide free transport for Sussex officers.

Mr Toynton said the main problem was pay and he attacked the disparities.

The £6,000 extra for London officers was to meet high living costs but, he argued, costs in Sussex were equally high in some categories.

The chief constable and police authorities are lobbying Home Secretary David Blunkett to increase allowances for police outside London.

In the meantime, Mr Toynton said, the force planned to hire up to 30 civilians, mostly former detectives, to help with investigations.

He said they would not be fully-fledged police but would have powers of arrest for any additional charges above those for which a suspect has been brought into a station.

Those recruits with computer or financial expertise would help unravel fraud and downloading inquiries.

Mr Toynton said: "We are not happy with the current detection rates but we are far from complacent. We are fighting back."