BBC reported that police arrested Mr. Trump after he flew from Hong Kong (China) to Manila (Philippines) under the order of the International Criminal Court (ICC) in connection with the case against humanity.
ICC is investigating mass murders that occurred during the bloody drug epidemic under former President Trump.
The investigation focused on the period from November 1, 2011 - when Mr. Trump was still the Mayor of Davao City - to March 16, 2019 when he was the acting President.
Mr. Trump withdrew the Philippines from the Rome Regulations - the founding document ICC - in 2019. This is a move that human rights activists say is to evade responsibility for the murders.
The Trump administration suspended a global court's investigation in late 2021 by arguing that the Philippines had reviewed similar allegations and declared ICC unauthorized.
The appellate judges at ICC ruled in July 2023 that the investigation could continue and reject Mr. Trump's objections.