DETECTIVES have called for more tests in their bid to find out how a Hampshire businessman died in the boot of a Rolls-Royce.

A full forensic investigation and a post-mortem have failed to establish the precise cause of Norman Carlton's death.

Now police are hoping that the results of new toxicology tests will aid their inquiries - although they say it may take some time.

Mr Carlton's body was discovered in the open boot of his champagne-coloured luxury car, which was parked outside Eastleigh civic offices, by a friend on Sunday morning.

It was understood that Mr Carlton, 53, ran the Call Carlton limousine hire company based at an address in Derby Road, Eastleigh.

Telephone calls to the company are being met with a recorded message saying: "Due to unforeseen circumstances, Call Carlton is closed until the first of April."

Mid-Hampshire coroner's officer, Roger Matcham, said an inquest into the death of Mr Carlton would be opening tomorrow or Friday.

It is believed Mr Carlton had not been living at his Eastleigh family home recently but had been staying at a hotel in the area.

His family declined to comment. Police are keeping tight-lipped about the circumstances of the case.

They have said it appeared that the dead man had been sleeping in his Silver Spur car but refused to say why he was doing so on one of the coldest nights of the year.

The Rolls-Royce, which had a personalised number plate, was reversed against a hedge near the former magistrates' court building in a car park opposite the civic offices in Leigh Road.

The investigation, codenamed Operation Oryx, is being carried out by the major crime department based at the police's western division headquarters in Hulse Road, Southampton.

A Hampshire police spokesman has said the inquiry team is currently not seeking anybody else in connection with the incident.

Det Insp Philip McTavish, who is working on the case, said: "We are doing a full investigation to fully review what happened and how he came to be there. That is going to take a little while."