His surprise arrest by Philippine police at the request of the ICC caused outrage among his army of supporters, who called it a kidnapping at the behest of a foreign court.

He has defended the anti-drug crackdown, and his legal team says his arrest was unlawful. The ICC maintains it has jurisdiction to prosecute alleged crimes committed before Duterte withdrew the Philippines from its founding treaty in 2019.

Despite the ICC’s case also including alleged killings of criminal suspects by a “death squad” in Davao while Duterte was mayor — which he has denied — analysts have said his arrest has only hardened support for him and his family, in Davao and beyond.

The former president’s two sons were also set to win posts on Monday, one re-elected congressman and the other winning the contest for Davao vice mayor and likely to serve in his father’s absence.

The family’s political resilience and dominance in Davao could prove pivotal as Duterte’s popular daughter, Vice President Sara Duterte, faces an impeachment trial that could see her banned from politics for life if convicted, killing off any hopes of a presidential run.

Asked earlier Monday about her father’s likely victory, she said plans would be made for him to be sworn in as mayor.

“The ICC lawyer said once we get proclamation papers, we will discuss how he can take oath,” she said.