A RESTAURANT worker accused of a double murder told a jury today that masked men burst in to their flat before the killings and tied him up.

Chinese graduates Xi Zhou and her boyfriend Zhen Xing Yang, both 25, were found with horrific injuries in August last year in Newcastle.

Guang Hui Cao, a 31-year-old restaurant worker, denies murdering them both, but told the jury he was blackmailed into unwittingly setting up the couple because of threats to his family.

He told Newcastle Crown Court he paid a deposit on a spare room in the couple's ground floor flat and was having a lie-in when a gunman burst in.

Speaking through an interpreter, he said: ''A person wearing a mask charged into my room holding a gun.

''He was wearing some sort of hood.

''He asked me not to move and to put my hands on my head and squat down, slowly.''

The defendant, also a Chinese national, said Mr Zhen, known as Kevin, was then brought in to the room at gunpoint by another man.

One of the gunmen then told Mr Zhen that he had made someone ''unhappy'', the jury heard.

The trial has heard told Mr Zhen and his girlfriend, known as Cici, had received threats over the internet, that they were involved in an internet football betting scam, and that they had made thousands of pounds from producing false qualifications.

Guang said: ''Kevin was terrified, he said 'I'm willing to compensate' in a trembling voice.''

The dishwasher was then taken to the bathroom where he was kept, bound by his hands and feet, for several hours, he said.

Later, he said he was taken out of the bathroom and saw Cici crouching down with her hands tied behind her back.

Guang said he saw a third robber was on a sofa looking at a computer.

He was told later he could leave, but was given the warning: ''When you leave here, be careful what you say and think about your parents.''

The defendant claimed a few days before the killings - before he had moved in to the couple's flat - he received threats from an anonymous caller who contacted him by leaving a mobile phone in an envelope outside his house.

The mystery voice said the telephone contained a file and urged Cao to look at it. When the defendant opened the file, he found an image of his parents in China.

Guang claimed the caller said: ''Have you ever imagined if a drunk driver drove his car forward (towards the couple), what would happen to them? Such incidents happen every day. Think it over.''

The caller knew Guang had already visited the couple's flat with a view to renting their spare room, and he was urged to take up the accommodation quickly.

Once he paid his deposit, Guang said he was told in a phone call to leave a key outside the flat.

The case was adjourned until tomorrow.