A friend of MI6 spy Gareth Williams, found dead after what police believe was a bondage sex game has said that the 31-year-old was not gay and was in fact studying for a new identity.

Williams, whose naked body was found padlocked inside a sports bag in August was a GCHQ code-breaker who was on secondment to MI6 at the time of his death. The key to the padlock was found inside the bag.

Police last week suggested that he died after a sex game went wrong but were unsure whether his partner was male or female. He had visited gay bars in Vauxhall and had purchased tickets to a drag show shortly before his death.

Sian Lloyd-Jones, 33, told the Mail on Sunday that before her friend died, he had been studying for a new identity and tat he was looking for a girlfriend.

She told the newspaper: “He said he was learning his new identity. It was all so relaxed. He often came round with his work. That night he came over with his box file and started going through it. He had two passports.”

Ms Lloyd-Jones added: “He was open with his family, and if he was gay and had any temptations he would have spoken about them, especially to his sister. Hand on heart, there were no innuendos about him.”

“He cherished the time he had with his sister and with me and he wanted that with other girls.”

William’s naked body was found locked inside a holdall at his Pimlico flat with the keys inside the bag. He is thought to have been dead for a week.

Last week, police said that he had visited bondage websites and had a £15,000 collection of women’s designer clothing.

Detective Chief Inspector Jackie Sebire, who is leading the inquiry, said she believes Mr Williams was locked in the bag by another person and that police would continue to study his private life for clues.

Speaking at New Scotland Yard today, she said: “We remain completely open-minded about how he died.

“We are appealing today to someone who is out there to come forward and tell us more.”

No traces of drugs or alcohol were found in Mr Williams’ body. Experts found that he would have died after 30 minutes inside the bag from suffocation.

Police are seeking a man and a woman who visited his flat several weeks before his body was found and say that forensic evidence shows that other people were in the property.

His death is still being treated as suspicious and unexplained and an inquest will be held in February.