A jealous body-builder killed a teenager he accused of chatting up his girlfriend in a nightclub, a jury was told.

Nicholas Sitko, 24, is alleged to have violently attacked Ben Lund, 19, at the Funktion Rooms, in Eastbourne, last summer.

Mr Lund, a window cleaner, of York Road, Eastbourne, suffered fatal brain injuries and died within seconds of the alleged brutal beating.

Sitko, a factory machine operator of Mendip Avenue, Eastbourne, denies murder at a trial at Lewes Crown Court.

CCTV footage from the club showing part of the alleged assault was shown to the jury at the start of the trial.

Sitko can allegedly be seen confronting Mr Lund before head-butting him.

Charles Miskin QC, prosecuting, told the court: "Ben Lund died because he was so severely battered around the head and neck he developed a major haemorrhage in the base of his brain which killed him.

"His killer was the defendant and the crime was committed because Sitko, a strongly-made body builder who had been drinking, thought Ben Lund had been chatting up his girlfriend Sarah Sharpe."

Mr Miskin described Sitko as being "obsessively jealous and insecure" in his long-standing relationship with Miss Sharpe.

He said at about 12.30am on July 11 the couple were in the basement Sub Club of the venue, in Pevensey Road, which has since closed down.

He said while Sitko was at the bar he believed Mr Lund was talking to his girlfriend and walked over to confront him.

He said: "He lost his self-control and was driven by a berserk desire to injure Mr Lund."

He said witnesses described Sitko attacking Mr Lund, who fell to the floor where he was beaten around the head and neck and left lying in a pool of blood.

Afterwards Sitko left the club but was arrested about an hour later. He was tearful and told police he wanted to talk to his mum.

He told police he had only acted in self-defence.

Mr Miskin said: "He lied because he knew what he had done could never be justified."

The trial continues.