SATV,12 MAR KATHAMANDU: Former Philippine President Rodrigo Duterte was arrested Tuesday on a warrant from the International Criminal Court accusing him of crimes against humanity, the Philippine government said.

Duterte was detained at Manila's international airport after arriving from Hong Kong, President Ferdinand Marcos' office said in a statement. The ICC has been investigating mass killings during the former president's deadly crackdown against illegal drugs.

"Upon his arrival, the prosecutor general served the ICC notification for an arrest warrant to the former president for the crime of crime against humanity," the government said. "He's now in the custody of authorities."

The surprise arrest sparked a commotion at the airport, where lawyers and aides of Duterte loudly protested that they, along with a doctor and lawyers, were prevented from coming close to him after he was taken into police custody. "This is a violation of his constitutional right," Sen. Bong Go, a close Duterte ally. told reporters.

The warrant of arrest sent by the ICC to Philippine officials, a copy of which was seen by The Associated Press, said "there are reasonable grounds to believe that" the attack on victims "was both widespread and systematic: the attack took place over a period of several years and thousands people appear to have been killed."

Duterte's arrest was necessary "to ensure his appearance before the court," according to the March 7 warrant, adding that the former president was expected to ignore a court summons.