Rights groups have said tens of thousands were killed in his antidrug campaign while he was the president of the Philippines.

The 79-year-old Duterte, the first Asian former leader arrested on an ICC warrant, was read his rights and formally informed of the charges of crimes against humanity that the court’s prosecutors filed against him after a lengthy investigation.

Former Philippines President Rodrigo Duterte has made his first appearance at the International Criminal Court in the Netherlands, where he faces murder charges related to his “war on drugs.”