A young Chinese couple could have been murdered for the large sums of money they made through selling dodgy qualifications and an internet betting scam, a court heard.

Xi Zhou and her boyfriend Zhen Xing Yang, both 25, were found dead in their flat in Newcastle last August having suffered horrific injuries.

Guang Hui Cao, 30, of Morpeth, Northumberland, denies two counts of murder at Newcastle Crown Court.

Robert Smith QC, prosecuting, said Miss Zhou, known as Cici and Mr Yang, also called Kevin, had mobile phones and a laptop computer taken from the flat they shared after they were murdered.

But he said the level of violence used was hard to explain as being "even remotely necessary" to take those items.

There was evidence that Mr Yang made a living selling false qualifications and that he also assisted in a fraudulent internet betting operation.

Mr Smith said: "He had very substantial sums of money passing through his and Cici's bank accounts.

"Whether this affords an explanation for the action of the person or persons responsible, it's certainly a realistic possibility, particularly if those facts became known to them."

The prosecution said Miss Zhou was seen on CCTV leaving work at a city centre noodle bar and then catching a bus home to Croydon Road in Fenham after a lunchtime shift.

No more than two hours after leaving work, she was dead.

Mr Smith said: "She met a violent and brutal death inside her own home where the man and any other persons who may have been responsible also killed her boyfriend Kevin in quite brutal circumstances.

"It is possible her boyfriend was already dead when she entered the house at about 4.10pm that afternoon."

She was quickly bound and gagged and placed face down on a bed, where she was to suffocate around 90 minutes later.

She was also struck about the head with a hammer, or a similar weapon, causing her skull to fracture.

Mr Smith said: "The death of Kevin was more brutal still."

He was placed on another bed in the property and hit about the head and face with a similar weapon. His throat was also cut with a knife.

Mr Smith said Miss Zhou was a Chinese national who came to this country in June 2005 as a student.

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