Inspector-general of police Khalid Abu Bakar has dismissed a report in The Australian newspaper that Sirul Azhar Umar could be subjected to harm or threats from Malaysia's special branch.

"There is no reason for us to harm or threaten him. This is absurd," he told Malaysiakini .

The report said Sirul, who was convicted in relation to the 2006 murder of Altantuya Shaariibuu, is now placed in solitary confinement at Sydney's Villawood immigration detention centre.

Apart from this, those visiting him are subjected to full security screenings by senior Australian Border Force officials.

The newspaper said the "extraordinary measures”were put in place due to fears for his safety.

Sirul landed in the media glare once again following the release of his purported video confession, where among others, he said Prime Minister Najib Abdul Razak was not involved in the case and that some were attempting to use him to engineer the latter's downfall.

So far, three parts of the video confession have been released to the media.

Last week, Malaysiakini quoted a source, who has viewed the full video, as claiming that the final part is the most explosive.

The source claimed that Sirul, a former police commando, had revealed the names of five individuals who allegedly attempted to bribe or coax him into implicating Najib.

Though the source did not reveal their identities, it is believed those named include both ruling and opposition politicians.

Meanwhile, Khalid said the police are investigating the video and the alleged confession.

"These are serious allegations. We will determine the veracity of the claims and check if the video is authentic," he added.

Sirul and another former police commando Azilah Hadri were initially acquitted of the murder but the Federal Court last January overturned the decision and sentenced the pair to death.

Prior to the apex court's judgment, Sirul fled to Australia, where the law prohibits the deportation of those facing the death penalty in their home countries.

He was detained on Jan 20 last year by Australian immigration after Interpol issued a red notice, and held at Villawood. He has since applied for a protection visa.