The police will investigate Al-Jazeera journalist Mary Ann Jolley over her report on the murder of Mongolian woman Altantuya Shaaribuu.

Inspector-general of police Khalid Abu Bakar said a probe would be initiated against the Australian-based journalist under Section 505(b) of the Penal Code related to "statements with the intent to cause, or is likely to cause, fear or alarm to the public."

The police chief also dismissed the allegations made in the Al Jazeera weekly programme 101 East, titled ' Murder in Malaysia '.

Among others, the report claimed Sirul Azhar Umar, one of those convicted with the murder of the Mongolian national, had attempted to blackmail Prime Minister Najib Abdul Razak.

This was purportedly based on messages extracted from the former police commando's mobile phone.

"Our investigation never showed there were attempts to blackmail the prime minister or anything of that sort," Khalid told Malaysiakini .

The police chief was also livid over the report which quoted an unidentified relative of Sirul alleging it was Abdul Razak Baginda who pulled the trigger in the grisly murder of Altantuya.

"This is utter rubbish," he thundered. "These are baseless allegations aimed at sowing confusion among the Malaysian public."

"Our probe was exhaustive and there was no evidence, be it physical or circumstantial, to show that Razak Baginda was at the scene of the crime," he added.

On the absence of a motive being established, Khalid said he had explained this issue numerous times.

"The court found no reason to establish one. I cannot speak on behalf of the courts on the reason for this.

"But there are cases where motive is not needed to secure a conviction in the face of evidence that prove beyond a reasonable doubt that the suspects committed the crime," he added.

'Is this another plot against PM?'

Quizzed on the need to deport Jolley, who is based in Australia, in the midst of her investigations, Khalid said the question should be referred to the Home Ministry and Immigration Department.

"I only wish to clarify that the allegations contained in the report are untrue and do not correspond with our investigations," he said.

"Furthermore, this case has been dealt with at the Federal Court level.

"So why is this issue resurfacing now? Is this another plot against the prime minister?" he asked.

Razak Baginda, who is a close associate of Najib, was charged with abetting the murder but later acquitted.

In January, the Federal Court overturned their acquittal and sentenced Sirul and another former police commando Azilah Hadri to death for the 2006 murder.

However, Sirul had fled to Australia before the verdict was delivered and is currently being held at an immigration detention centre in Sydney.

The Malaysian government's bid to extradite him hit a brick wall as Australia does not deport those who face the death sentence in their home countries.

Najib has repeatedly denied any involvement in the case or that he had met Altantuya.