A killer on trial for the murder of a mum who was burned alive in her abandoned car has told jurors his 'deranged' co-accused committed the crime.
Stephen Unwin and William McFall, who are both already convicted murderers and met while serving life sentences, are accused of killing Quyen Nguyen after keeping her captive at a house for four hours where she was raped and forced to hand over bank details.
Unwin has told jurors he left McFall, known as John, alone with the victim at his home while he went to the shop for cigarettes and that she looked "dead" when he got back.
But on his first day in the witness box, McFall has told jurors at Newcastle Crown Court it was Unwin who carried out the killing last August .
McFall said Unwin “laughed” when he single handedly carried out the attack and added: "It was a joke to him."
McFall told jurors what happened at the house that night was a 'living nightmare' which started when Miss Nguyen arrived for a business meeting with Unwin.
He said he saw his former cell mate drag Miss Nguyen to the floor where a pillow case and plastic bag were put over her head and where Unwin said he was going to have sex with her.
McFall said he begged Unwin to stop the attack but added: "I couldn't stop him. There was no reasoning with him whatsoever."
He told jurors: "I heard her say ‘help me’ a few times and said 'please let her go', I said 'enough is enough man'."
The 51-year-old said Unwin was naked, 'deranged' and laughed during the attack and added: "It was a joke to him."
He told jurors: "He smothered her and left her lifeless on the floor, where I believed she was dead."
Miss Nguyen and her car were dumped and set on fire at a dirt track, while she was still 'just alive'.
Jurors at Newcastle Crown Court have heard both men initially denied any involvement in Miss Nguyen's death but now blame each other for her killing.
They have heard Miss Nguyen's body was found in her Audi A4 which was dumped and set on fire on a dirt track near Sunderland.
The 28-year-old nail salon worker may have been still alive when the blaze was started and could only be identified through dental records.
Unwin, 40, of St Oswald's Terrace, Houghton, and McFall, 51, of Waterloo Road, Blackpool, both deny rape and murder.
Jurors have heard Unwin was given a life sentence in 1999 for murder after he broke into a 73-year-old man's home in Houghton on Christmas Day in 1998 and attacked then stabbed him in the chest before starting three fires.
He was released in 2012.
The court heard McFall was jailed for life at Belfast Crown Court in April 1997 after he had broken into the home of 86-year-old Martha Gilmore, who had mobility problems, at Station Road, Greencastle, and repeatedly hit her with a hammer in May 1996.
McFall was released on licence in 2010.
Both men deny the murder and rape of Miss Nguyen.
The trial continues.