One of the victims of a brutal double murder may have used forged documents to con a British University.

Zhen Xing Yang, who with his girlfriend Xi Zhou, both 25, was found dead with horrific head injuries in their flat in Newcastle's West End on August 9, dropped out of a Cardiff University undergraduate degree course in 2005.

He then gained a place on a post graduate course at Newcastle University, gaining a masters degree in 2006.

It is understood Newcastle University is investigating the alleged forged qualifications.

Mr Yang, known as Kevin, was tortured for up to an hour before he was hacked and stabbed to death by his killers, who then turned on Wagamamas noodle bar waitress Xi Zhou.

Internet users on UK-based Mandarin websites had identified Mr Yang as a recruitment agent for a gambling racket which relied on the results of live Premier League football games being shown a couple of minutes later in China to beat the bookies.

Police became aware of Zhen Xing Yang's links to alleged passport forgery, fake visa and qualification documentation, and an internet football betting scam early in their investigation into his murder.

Det Supt Steve Wade, who is heading the inquiry, said: "A possible motive for the killings is beginning to emerge concerning the lifestyle of Xi Zhou and Zhen Xing Yang.

"The male victim may have been involved in betting scams and the arrangement of fraudulent documentation, such as visas and qualifications.

"Community intelligence supported by the examination of computer equipment and mobile call data has shown that both of the victims have been involved in fraudulent activity which has angered and upset a number of people.

"We are currently investigating this as a possible motive for the killings."

A woman relative, speaking on behalf of Mr Yang's mother said the mum, in her 50s, was devastated by her son's murder.

She said: "She is trying to sort out paperwork and documentation to enable her to come to England to be with her son's body.

"She had paid out a lot of money for him to come to England for his education. Reports about her son's death have made her even more distressed."

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