Security guard stabbed to death by drug dealer in 'scene from Psycho'

David Watson, 20, had been taken to an office to be interviewed after he was stopped on suspicion of stealing a £15.99 CD in a shop.

He is said to have suddenly lost his temper and produced a kitchen knife which he plunged into father-to-be Paul Cavanagh, 30, before stabbing another security officer in the back.

Shoppers scattered as he fled the Chapelfield shopping centre in Norwich and ran through the city centre streets, covered in blood.

An off-duty special constable was allegedly slashed with the knife when he tried to give chase before Watson finally dropped the knife and gave himself up to police.

Another store detective, Gary Locke, later told officers: "It looked like something out of the film Psycho. I have never seen anything like it."

One of the most dramatic moments on the first day of the trial was when jurors were shown CCTV footage of Mr Cavanagh struggling to restrain Watson in the office.

Norwich Crown Court heard that Watson, of Hackney, north London, was a drug dealer who had travelled to Norwich because it was easier to sell there.

He had been wandering through an HMV store in the shopping centre on December 18 last year when he was detained on suspicion of stealing a music CD.

When he was taken to a room to be questioned he allegedly took the knife from a bag, wielding it 'like a dagger', before stabbing Mr Cavanagh, of Rockland St Mary, near Norwich, whose fiancee was pregnant with their first child.

The six-inch deep wound sliced through the store detective's voice box and severed his right jugular vein. He died shortly afterwards.

Prosecutor Graham Parkins told the jury: "It was a vicious and brutal attack on an unarmed man who was merely doing his job."

Another security guard, Gavin Levett, 34, tried to escape back to the shop floor but was stabbed in the back, leaving a one-inch long wound.

Watson then fled onto the packed pre-Christmas city centre streets.

Mr Parkins added: "The knife was in full view. He was holding it high over his head like a trophy, like he wanted to show people he had used it."

Off-duty special constable Ian Gardiner managed to corner Watson on a multi-storey car park staircase, the jury heard, but gave up the chase when he, too, was slashed with the knife.

Watson finally dropped the weapon in a supermarket car park and gave himself up to officers minutes later in a nearby street.

He is alleged to have later told a prison officer at Norwich jail, where he was on remand awaiting his trial, that he had been worried police would find £10,000 of crack cocaine in a carrier bag he had when they arrived.

He went on to tell the prison officer that he had taken out the knife to scare the security guards into letting him go.

Tests later revealed traces of cocaine and diamorphine in the bag.

Watson denies murdering Mr Cavanagh, wounding Mr Levett with intent to cause grievous bodily harm and attempting to wound Mr Gardiner with intent.

The case continues.