The case could become a political hot potato when it resumes in January, as investigator P. Balasubramaniam and blogger Raja Petra Kamaruddin have made controversial allegations about Datuk Seri Najib and the victim, Ms Altantuya Shaariibuu.

Mr Balasubramaniam had alleged that MrNajib had sexual relations with her, while Raja Petra claimed that Mr Najib's wife was present when Ms Altantuya's body was blown up with explosives.

Her remains were found in a jungle clearing outside Kuala Lumpur in 2006.

This case, with its brew of politics, sex and murder, gripped Malaysia after the Deputy Premier's close associate, Mr Abdul Razak Baginda, was charged with instructing two policemen to kill Ms Altantuya.

Mr Abdul Razak, who said Ms Altantuya was his former lover, was acquitted recently but policemen Sirul Azhar Umar and Azilah Hadri have been ordered to make their defence.

Mr Najib, expected to become Malaysia's premier next March, has repeatedly denied knowing Ms Altantuya but the scandal has continued to dog him.

His Umno party has stood solidly behind him. When its divisions completed making their nominations for the party presidency last weekend, they overwhelmingly chose Mr Najib except for one other nominee, Kelantan prince Tengku Razaleigh Hamzah.

So far, there has been no proof to link MrNajib to this case.

Mr Balasubramaniam has been missing for the last few months since he retracted the allegations he made against Mr Najib.

'The investigating officer has said he is trying to trace where he is. We do not know his whereabouts,' defence lawyer Kamarul Hisham, who represents Sirul Azhar, told the court yesterday.

He also said he wants Raja Petra to testify about his statutory declaration in which he claimed that Mr Najib's wife, Madam Rosmah Mansor, was present when explosives were placed on Ms Altantuya.

He said he was trying to contact the blogger, who was released last week after being detained under the Internal Security Act. Raja Petra was in another court yesterday, facing a sedition charge over a blog posting implicating Mr Najib in the Altantuya case.

Lawyer Hazman Ahmad, who represents Azilah, plans to call Mr Najib's senior security aide as a witness. According to court evidence, it was the aide, Mr Musa Safri, who introduced Azilah to Mr Abdul Razak after the latter sought his help, saying that Ms Altantuya had been harassing him.

Neither Mr Najib nor Mr Abdul Razak is expected to be called as a witness.

The lead prosecutor, Tun Majid Hamzah, told The Straits Times that the prosecution has up to Friday to file an appeal against the acquittal of Mr Abdul Razak. It has not decided whether to do so.

carolynh@sph.com.sg