Former Philippines President Rodrigo Duterte was detained on Tuesday under an International Criminal Court arrest warrant, which accused him of crimes against humanity in connection with the brutal “war on drugs” he led while in office, the Philippines Presidential Communications Office said.

Members of the Philippine National Police met the former president as he arrived in Manila, the capital, on a flight from Hong Kong, the office said.

Duterte carried out an extensive “war on drugs” after taking office in 2016. Independent rights organizations have accused him of overseeing a crusade of extrajudicial killings, many of which were alleged to have been carried out by so-called “death squads.”

More than 12,000 people were thought to have been killed, according to Human Rights Watch.

Officials in Manila said they received a copy of an ICC arrest warrant via Interpol on Tuesday morning. Dozens of officers swarmed Ninoy Aquino International Airport to arrest Duterte as he and his aides arrived at about 9:20 a.m., the presidential office said.

“The former President and his entourage are in good health and have been examined by government doctors,” the office said in a statement posted on social media in Filipino. “They have assured that he is in good condition.”

The ICC began an investigation into Duterte’s “war on drugs” in September 2021. The Philippine government that year sought to put an end to the probe, a request that was denied in 2023 by Karim A.A. Khan, the ICC prosecutor, according his office.

Khan in rejecting the request pointed to an investigation by the Philippine Commission on Human Rights into police and state activities carried out under the “war on drugs” between 2016 and 2021.

That investigation found that the government “failed in its obligation to respect and protect the human rights of every citizen, in particular, victims of drug-related killings” and “has encouraged a culture of impunity that shields perpetrators from being held to account,” Khan wrote, citing the rights group.

The ICC focused its investigation on Duterte’s actions between 2011, when he was a local mayor, and 2019. During those years, Duterte and other high-level government officials “reportedly encouraged, supported, enabled, and excused the killing of drug users and drug dealers,” the ICC prosecutor said in a filing.

Duterte, who is now 79, swept into national office from Davao City, where he had been mayor, with a promise to curb crime and corruption.

His methods for fighting illegal drug use had been described as “unorthodox” and on the verge of “the illegal,” he said in his inaugural address in 2016.

“As a lawyer and a former prosecutor, I know the limits of the power and authority of the president. I know what is legal and what is not,” he said in that address. “My adherence to due process and the rule of law is uncompromising.”

ABC News’ Andrew Evans and Karson Yiu contributed to this report.