A Malaysian detective has gone missing after retracting allegations he made linking Deputy Prime Minister Najib Razak to the brutal murder of a Mongolian woman, police said on Saturday.

The allegations and the retraction came amid a flurry of political scandals gripping the Southeast Asian country.

The detective, P. Balasubramaniam, retracted the allegation after Najib denied again on Thursday that he had ever met the victim, Altantuya Shaariibuu.

One of his top political advisers, Abdul Razak Baginda, is being tried on charges of abetting the murder of the woman, who was shot in the head twice and her body blown up with explosives in 2006.

"We will be calling up several people to assist us to locate the private investigator," federal police deputy chief Ismail Omar was quoted by the online edition of the Star newspaper as saying on Saturday. "We have no idea where he is."

Najib denied he ever had a sexual relationship with the Mongolian, or had conspired to cover up her murder, allegations made on Thursday by Balasubramaniam, who was working for Abdul Razak at the time of the murder.

Balasubramaniam issued a legal deposition on Friday saying he was retracting "the entire contents" of his earlier statement, which was made "under duress".

The flurry of accusations and denials are stemming from a high-stakes battle for power in Malaysia, featuring allegations of sleaze and murder.

In another political scandal that has rocked Malaysia, main opposition leader Anwar Ibrahim is accused of sodomising his aide. Sodomy is a crime punishable by up to 20 years in jail.

Anwar has rejected the allegation made by the aide last week as a top-level conspiracy to keep him from running for parliament and stymie his drive to woo defectors from the ruling coalition.

Najib and Anwar are rivals to succeed Prime Minister Abdullah Ahmad Badawi.

Anwar said on Thursday the sodomy allegations surfaced because leading government figures feared he would use the detective's allegations in the Altantuya case in his drive to lead the opposition to power for the first time in Malaysia.

He had previously said the sodomy case emerged to stop him running for parliament in a by-election, a necessary first step toward becoming premier.

The three-party opposition alliance made historic gains in a March election, winning five of 13 state governments and coming within 30 seats of taking control of the 222-member parliament.