Former Philippines President Rodrigo Duterte was arrested Tuesday in Manila by police acting on an International Criminal Court warrant tied to his deadly war on drugs.

The 79-year-old faces a charge of "the crime against humanity of murder," according to the ICC, for a crackdown that rights groups estimate killed tens of thousands of mostly poor men, often without proof they were linked to drugs.

"Early in the morning, Interpol Manila received the official copy of the warrant of the arrest from the ICC," the Philippine Presidential Palace said in a statement.