A millionaire heir to a food company fortune has been found guilty of the callous knife murder of his "loyal" best friend.

Dylan Thomas, 24, the heir to the Peter's Pies company fortune, has been found guilty of murdering his best friend on Christmas Eve by a jury at Cardiff Crown Court.

Sir Stanley Thomas, the founder of Peter’s Pies, whose net worth was estimated to be £230m in 2013, sat in court throughout the trial.

Thomas was described to the jury as being "something of a loner" while Mr Bush was more outgoing and active. His brother called him a "loyal" friend.

Mr Bush sustained 37 stab wounds in the attack, including 16 to the neck, while Thomas had cuts to the palms of his hands, which he told police he received while trying to defend himself.

William Bush was stabbed to death on Christmas Eve (
Image:
WALES NEWS SERVICE)

Thomas appeared before Cardiff Crown Court on Thursday by video link from Ashworth Hospital Liverpool, where he is in custody and being treated for schizophrenia.

During the trial, the jury heard from Dr Panchu Xavier, a consultant forensic psychiatrist at Ashworth, who said the defendant could have been having a psychotic episode during the attack and for "up to six months before the event".

The jury also heard Thomas had been arrested for breaking into Buckingham Palace a few months before the attack on Mr Bush.

Thomas told officers he was looking for "energy fields" between the palace and Cleopatra's Needle, an obelisk in central London.

Police at the scene of the murder (
Image:
WALES NEWS SERVICE)

He was rugby-tackled by an officer after he told them he was "over now so you may as well show me round".

Sending the jury out on Thursday, judge Mrs Justice Steyn KC said they could take as long as they need to reach a verdict in the case. They returned in a matter of hours.

The defence argued throughout the case that Thomas was mentally unwell at the time of the incident, saying there was a "gamut" of signs of psychosis.

Trial judge Mrs Justice Steyn said she would pass sentence on December 16.

Thomas was remanded into custody.