Philippine lawmakers questioned the alleged illegal arrest of drugs war strongman Rodrigo Duterte by the International Criminal Court (ICC).

Senator Imee Marcos, the older sister of President Ferdinand Marcos Jr. who is also called Bongbong, grilled high-ranking security officials over the 'divisive' arrest in a hearing on March 20.

Footage shows former army chief Eduardo Ano and police director Nicolas Torre III appearing before the senate panel chaired by the elder Marcos sibling. They both defended their role in Duterte's capture.

Eduardo, a former Duterte Cabinet member who now serves as the National Security Adviser, said: 'The implementation of the ICC warrant is beyond my mandate and I have no part in it. And may I also state for the record that I am not aware of any core group, nor am I a member of such group that allegedly planned and prepared for the arrest of former President Duterte. It is utterly unacceptable and unfair that my name is being dragged into an alleged grand conspiracy. I firmly deny any allegations of a grand conspiracy.'

Imee Marcos is a staunch ally of the Duterte clan and is the elder sister of Bongbong, who is accused of permitting Duterte's ICC arrest. Despite denying claims of a sibling feud, she has repeatedly opposed her younger brother in clashes between the two powerful political families.

Duterte - who once boasted of throwing a rival out of a helicopter to his death - was arrested on March 11 morning at the Ninoy Aquino International Airport on a warrant issued by the ICC in the Hague.

He had initially refused to disembark the plane upon arrest, telling officials: 'You will just have to kill me. I refuse if you will just ally with the whites.'

He was later seen boarding a police vehicle with his wife Honeylet Avancena and daughter Veronica. He had returned to the country on Cathay Pacific flight CX907 after meeting with overseas Filipino workers in Hong Kong a day earlier.

Philippine President Ferdinand Marcos Jr., a former ally and now political rival of the influential Duterte family, defended the government's role in the strongman's arrest.

He said: 'Interpol asked for help and we obliged because we have commitments to Interpol which we have to fulfil. If we don't do that, they will no longer help us with other cases involving Filipino fugitives abroad. We cannot say no to Interpol when they ask us to catch a wanted individual.'

Duterte is the architect of the country's notorious bloody war on drugs, which police claimed saw more than 6,000 drug suspects killed. However, human rights groups said the alleged extrajudicial executions reached up to 30,000.

In 2018, Duterte withdrew the Philippines from the ICC after it began investigating alleged human rights abuses linked to his war on drugs. He had argued that the ICC had no jurisdiction over the Philippines and accused it of being biased.

The ICC has set the confirmation of charges hearing for Duterte on September 23.