An Eastbourne father was permanently blinded in a savage attack by a man who believed he was killing an alien, a jury heard.

Clifford Williams, who has five children, was repeatedly beaten with a metal bar and left lying in the street in a pool of blood.

Homeless Ian Punyer, 35, denied attempting to murder him on the grounds of insanity.

The jury at Lewes Crown Court heard Punyer accepted he assaulted Mr Williams, 53, but said he was insane at the time of the attack in Eastbourne in April last year.

Mr Williams, of Bexhill Road, Eastbourne, who ran a computer business before the attack, was in court.

Still visibly scarred, he sat in the public gallery and was comforted and supported by his partner, Sandra, who held his hand while the graphic details of his injuries were described.

Philip Meredith, prosecuting, told the jury their role was to decide Punyer's state of mind at the time of the assault, after hearing evidence from psychiatrists.

He said: "There is no dispute as to what he did. The single issue is whether he was insane."

Mr Meredith said Punyer told police he believed he was attacking an alien.

He said: "He believed he was protecting himself and the world from an alien, the Tin Man. Regrettably, in human terms, that was Mr Williams."

Mr Meredith said Mr Williams, a motorcycle enthusiast, was in his garage in Seabeach Lane when Punyer, who he did not know, walked in at about 8.30pm and started to pick up items, including a plastic sheet.

Mr Williams has difficulty remembering what happened but witnesses saw Punyer, wrapped in a plastic sheet, attacking him in nearby Seaford Road with a metal 2ft jack handle.

He was seen standing over Mr Williams, who was lying on the ground, beating him repeatedly over the head, face and body.

Mr Williams, who was in a critical condition, was rushed to hospital with severe head injuries.

He had multiple injuries to his face, including cuts and a torn ear. He suffered fractures to his skull, cheekbones, nose and jaw. He also had a broken wrist and finger and had lost some teeth.

He was in a coma for three weeks and stayed in hospital for ten weeks. Despite a series of operations, he will be permanently blind.

Punyer walked away after the attack and police found him shortly afterwards curled up in a foetal position covered in a plastic sheet.

He was muttering and rambling, telling officers: "The aliens are coming. Plastic polythene is the only protection against the Tin Man. I have done the Tin Man. There has been a murder. I killed him. He was killed because he was an alien."

The case continues.