An Arab billionaire’s son wanted for questioning over the death of a Norwegian socialite had been ordered by his father to tone down his playboy lifestyle, The Times has learnt.

Farouk Abdulhak had been told that he risked being cut off from his family after his father, Shaher Abdulhak, learnt of his wild behaviour as a student in London. His father feared that his partying and drinking was interfering with his education at Regent’s Business School and could tarnish the family’s reputation in his native Yemen.

Mr Abdulhak, 21, was seen leaving an exclusive Mayfair nightclub with a fellow student, Martine Vik Magnussen, 23, on the night she disappeared. Her partially clothed body was found two days later hidden in the basement of his apartment block.

Detectives appealed yesterday for help in tracing designer clothing and jewellery that was missing when Miss Magnussen’s body was found on Sunday. The items include a Guess watch, her Marc Jacobs handbag and snake-skin shoes, one of a pair of Christian Dior earrings, a pair of jeans and a costume, silver-coloured, diamond ring.

A friend of the family suggested yesterday that Mr Abdulhak was struggling to balance his family’s conservative roots and the Western lifestyle that he enjoyed as a student living abroad.

“He was being groomed to take over the family business. He was under a lot of pressure to uphold his family’s honour,” said the friend, who did not want to be identified, fearing that he would be punished for betraying the Abdulhaks by speaking to the press.

On a social networking website Mr Abdulhak said that he both drank and smoked and described himself as an agnostic.

The student is believed to have fled Britain on Saturday to Yemen, where his father runs a powerful oil and tourism empire that spans the Middle East and North Africa.

Detective Chief Inspector Jessica Wadsworth said: “The death of Martine remains unexplained and is the subject of further scientific testing. We wish to interview Mr Abdulhak as a matter of urgency to further investigate what happened to Martine in her final hours and how her death came about. We believe he holds important information.”

However, Abdul Kader Mohammed Kahtan, director-general of the Interpol agency in Yemen, said that the British authorities had not yet contacted him regarding the case. “I didn’t receive any information, but will cooperate with the police if they give a request for an investigation,” Mr Kahtan told The Times. Even if Mr Abdulhak were to be apprehended in Yemen, the country’s Constitution expressly forbids the local authorities from extraditing a citizen, regardless of circumstance. Article 44 of Yemen’s Constitution states: “A Yemeni national may not be extradited to a foreign authority.”

The law requires all nationals to undergo trial in Yemen, where the legal system is a mixture of Sharia and tribal law and where murder is punishable by death.

No Yemeni national has ever been tried for a crime alleged to have occurred in a European country. Western diplomatic sources suggested that any request to extradite Mr Abdulhak was likely to be rebuffed.

Mr Abdulhak’s family indicated that they would disown their son if he were found responsible for Miss Magnussen’s death. His father says that he has no idea as to his whereabouts.

A Western diplomatic source said of Mr Abdulhak’s case: “If the father decides his son will not be touched, he will not be touched. He will be completely protected.”

Considered to be among Yemen’s most powerful and politically well connected men, Shaher Abdulhak– who is known as the “King of Sugar” – founded the Shaher Trading Company in 1963.

Today he owns interests in the Yemen International Bank and the upmarket Sheba hotel in Sanaa. Despite his prominent position in Yemeni society, Mr Abdulhak’s father is notoriously publicity-shy. His photograph has never appeared in the local press. He rarely grants interviews and keeps an extremely low profile.

Mr Abdulhak is one of several siblings who were all educated abroad. He attended the elite Azal Hadda primary school before being sent to British boarding schools to continue his education.

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