A man has been re-arrested by police investigating the disappearance of 70-year-old Robert Saint, who is feared murdered.

Mr Saint vanished while trying to sell his boat at Birdham Pool, near Chichester, eight days ago. Police fear he was killed and dumped overboard.

Police today re-arrested a 44-year-old Bognor man who was released without charge earlier this week.

He was arrested at 8am and was being questioned at Chichester police station.

Meanwhile the Royal Navy has been called in to help in the hunt for the missing businessman.

Officers yesterday revealed they had found Mr Saint's wallet washed up on an Isle of Wight beach and a search of his boat Sundowner had revealed bloodstained clothing.

Detective Chief Inspector Tony O'Donnell said his team had been charting the movements of the 42ft boat as it moved around the Solent last Thursday.

He said: "Sundowner is a distinctive boat - only four of its kind were built. I'm asking people to remember if they saw Sundowner in the Solent or at Birdham Pool or Itchenor."

Mr Saint's wallet was spotted by a woman on a day trip on Tuesday.

Forensic teams scouring the galley of the Sundowner, which was found moored at Itchenor, have recovered a blood-stained shirt which they believe belongs to Mr Saint's killer.

Mr Saint, who lived in Horsham Road, Steyning, is thought to have driven to Birdham Pool with the intention of selling the yacht to a cash buyer for £119,000.

The boat is believed to have left Birdham at around 1.30pm.

Detectives are continuing to appeal for sightings of Mr Saint during the past week.

He looks younger than his 70 years and has silver hair with a balding patch on top, a beard and moustache, blue eyes and a light tan.

He is 5ft 7in and was wearing a grey and white jumper with a navy blue cravat, a gold neck chain with a seal pendant, a blue and white striped shirt and brown moccasins.

Anyone with information should call Operation Score on 0845 6070999.