In the latest episode of the ongoing political drama, Dr Mahathir Mohamad said those who do not support Prime Minister Najib Abdul Razak are being "threatened".

Though he did not elaborate, the former premier is believed to be referring to his son Mukhriz ( right ), who has been asked to resign as Kedah menteri besar should he fail to endorse the current leadership.

This morning, Najib's cousin and Umno vice-president Hishammuddin Hussein warned that Mukhriz must ensure that Kedah Umno does not split over this issue or else the latter would fail as a leader.

Mukhriz came under fire from Kedah Umno state assemblyperson Ahmad Lebai Sudin following a meeting with the menteri besar at his official residence yesterday.

It was reported that Mukhriz had reserved his support for Najib pending the outcome of the probe into 1Malaysia Development Berhad (1MDB).

However, another state assemblyperson dismissed this and revealed that the menteri besar is torn between his father and Najib .

Mukhriz himself announced that a decision on the issue would be revealed on April 24.

Meanwhile, in his latest blog post, Mahathir once again reiterated that he was not accusing Najib of having a hand in the murder of Altantuya Shaariibuu.

"I was only asking who gave the order to (former police commando) Sirul Azhar Umar.

"Usually, the police or army do not shoot dead people unless they are attacked or instructed to do so.

"This is a human life. If (Sirul) is wrong, kill Sirul. But if he was doing his duty and following orders, then it is not fair for Sirul to be killed," he said.

Mahathir said while the people do not question this issue, many have asked him about it.

"I cannot answer. So I ask the person who can answer," he added.

Last Thursday, Najib, in a pre-recorded interview aired on TV3, reiterated that he did not know Altantunya, who was murdered in 2006.

The police had also previously cleared the prime minister of any involvement in the case.

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