An alleged killer sweated and twitched as he wrote a dud cheque for the luxury boat he was obsessed about, a court heard.

Train guard David MacBride, 44, of Bramber Close, Bognor, has denied murdering 70-year-old Robert Saint after trying to buy a 42ft motor cruiser from the pensioner.

Pub landlady and Saint family friend Cynthia Foulkes was present when the rail worker gave Mr Saint a £119,000 cheque for his boat, The Sundowner, on September 24 last year.

MacBride, who earns £18,000 a year, told police he found the money for the boat on a train but it is alleged he killed Mr Saint, of London Road, Steyning, after the cheque bounced.

At the hearing in Lewes Crown Court yesterday, Jonathan Fuller, defending, cross-examined Mrs Foulkes about MacBride's tense appearance and his agitated reaction to being introduced to a harbour master at Birdham Pool, where The Sundowner was docked.

Mr Fuller said to Mrs Foulkes: "You were unfamiliar with my client's mannerism and temperament. You noticed he had a slightly nervous tic, a twitch, and also that he perspired heavily.

"Having asked you about what a harbourmaster does, it might be fair to simply recognise this was more curiosity than anxiety."

Mrs Foulkes replied: "In the manner it was asked, it was more anxiety than curiosity. I did not know the gentleman, I just observed the way he was."

Mr Saint, known as Captain Bob at Birdham Pool, never returned after a meeting to discuss the dud cheque.

His body was found ten days later on a beach in the Isle of Wight.

Mr Saint's head, which was fatally fractured from 16 blows by a blunt instrument, was wrapped in two plastic bags.

MacBride was arrested on September 27 after Mrs Foulkes and Mr Saint's son Glen, 49, called police because they could not find the pensioner.

The rail worker said he gave Mr Saint £119,000 in used £50 notes on the day he disappeared before taking him on The Sundowner to Portsmouth harbour.

Port radar records indicated The Sundowner actually went south, towards the Isle of Wight, instead.

Forensic scientists found a shirt covered in MacBride's DNA and Mr Saint's blood on the boat. Splattered blood was also found in its engine room.

The trial continues.