A drug dealer with a history of violent outbursts stabbed an unarmed Norfolk security guard to death in a “vicious and brutal attack” after being caught shoplifting, a court heard today.

A drug dealer with a history of violent outbursts stabbed an unarmed Norfolk security guard to death in a “vicious and brutal attack” after being caught shoplifting, a court heard today.

David Watson, 20, of Hackney, east London, stabbed Paul Cavanagh, 30, in the neck after being stopped in the HMV store in Chapelfield in Norwich in December 2006 for taking a £15.99 CD.

Prosecutor Graham Parkins QC told Norwich Crown Court Watson then stabbed a second security guard in the shoulder and attempted to slash an off-duty policeman trying to detain him.

One witness described the incident as “like something out of the film Psycho”, jurors were told.

“He was a wholly innocent man, simply doing his job,” said Mr Parkins.

“This was a vicious and brutal attack on an unarmed man.”

Watson denies murder, wounding with intent and attempting to wound with intent.

The trial continues.