Model Altantuya Shaariibuu was found shot dead in 2006
Malaysian police have launched an international hunt for a private investigator who accused a top politician of sexual misconduct.
Balasubramaniam Perumal vanished after retracting a claim that Deputy Prime Minister Najib Razak had sex with a Mongolian woman later found murdered.
Mr Najib, who is locked in a political struggle with rival Anwar Ibrahim, has denied any link to the woman.
Police believe the missing investigator is in hiding.
The murdered woman, Altantuya Shaariibuu, worked as a model. Her remains were found outside the Malaysian capital Kuala Lumpur in October 2006.
She had been shot twice in the head and her remains blown up with plastic explosives.
Abdul Razak Baginda, a political advisor to Mr Najib, is on trial accused of abetting her killing.
Last Thursday, Mr Balasubramaniam caused a sensation by stating in a sworn declaration that he had been told Mr Najib had had sex with Ms Shaariibuu.
Mr Najib denied any link to the model at a news conference the same day.
Najib Razak says he is the subject of a malicious lie
The claims were, he said, "a terrible lie, a malicious fabrication" designed to tarnish his image.
On Friday, Mr Balasubramaniam announced he was withdrawing his allegation completely, saying it had been made under duress. He then disappeared along with his wife and children.
Malaysian police have now asked Interpol to assist in finding the missing investigator.
"I give a guarantee of his safety if he comes to meet us and he is free to bring a lawyer to the meeting," Malaysian Criminal Investigation Department director Bakri Zinin told reporters on Sunday.
"The police in the country have been put on alert to find him. We have informed Interpol... as well as the police in neighbouring countries."
Mr Najib is seen as a strong contender to succeed Malaysia's Prime Minister Abdullah Ahmad Badawi as the country's next leader.
His chief rival, opposition leader Anwar Ibrahim, has also been accused of sexual misconduct in a separate case which has gripped the mainly Muslim country.
Having served six years in prison for sodomy and corruption, then seen the sodomy count overturned, Mr Anwar has been accused again of having sex with a young man.
He denies the charge and says he is the victim of a conspiracy.