Why was former President Duterte arrested?

Manila [Philippines], March 12: Former Philippine President Rodrigo Duterte was arrested on March 11 as he ran to regain the mayorship of Davao City in midterm elections in May.
Former Philippine President Rodrigo Duterte was arrested by police at Manila's international airport on Tuesday after returning from Hong Kong, following an order from the International Criminal Court (ICC) over his bloody war on drugs. The Philippine presidential communications office confirmed that Interpol had received a formal arrest warrant from the ICC. Meanwhile, Salvador Panelo, Duterte's former chief legal adviser, called the arrest "illegal," according to AFP.
Accusations against Mr. Duterte
Former President Duterte was arrested while facing an ICC case over alleged crimes against humanity in his anti-drug campaign, when he was mayor of Davao and then president of the Philippines (2016-2022). The Philippine Daily Inquirer cited several reports that the anti-drug campaign killed at least 6,000 people, but human rights groups say the number could be as high as 20,000.
The Philippines withdrew from the ICC in 2019 at the behest of Mr Duterte, but the court retained jurisdiction over the killings before withdrawing. The ICC investigation was suspended for nearly two years before resuming in July 2023 after a five-judge panel rejected the Philippines' objection that the ICC had no jurisdiction.
During his campaign against drugs, Mr. Duterte instructed police to shoot to kill suspected drug dealers if their lives were threatened. When the Philippine Senate opened an investigation into the drug war in October 2024, Mr. Duterte declared "no apologies, no excuses" for his actions.
Former President Duterte remains popular with many Filipinos who support his quick-fix crime-busting solutions, and he remains a powerful political force, according to AFP. Mr Duterte is running to regain the Davao mayorship in midterm elections in May.
The confrontation between the two families Duterte - Marcos
The ICC investigation into the Philippines' anti-drug campaign is being used as a political football between the Marcos and Duterte families , according to a commentary posted on the Justice Info website .
Incumbent Philippine President Ferdinand Marcos Jr. (son of the late President Ferdinand Marcos Sr.) and Vice President Sara Duterte (daughter of former President Duterte) formed an alliance and won the 2022 election. However, the "unity" of these two figures at that time was just a political compromise without a common foundation.
The rift began when Mr. Marcos appointed Ms. Duterte to double as education minister, despite her preference for the defense ministry. Ms. Duterte also faced several allegations of her office misusing intelligence and secret funds. In response, Ms. Duterte publicly threatened to assassinate Mr. Marcos, and her father accused Mr. Marcos of being a drug addict.
Meanwhile, President Marcos and his allies are continuing to investigate the mishandling of funds by Mrs. Duterte's office. They are also scrutinizing the bloody war on drugs under the former President Duterte's administration.
Therefore, in a recent commentary published on The Interpreter , the Lowy Institute (Australia) said that the midterm elections in the Philippines in May will not only evaluate the administration of President Marcos but also decide the political survival of Vice President Duterte. "This will be an example of the ongoing hostility between the two most prominent political families in the Philippines," the Lowy Institute commented.
Source: Thanh Nien Newspaper