The Philippine justice secretary said Friday that any investigation violating the country's sovereignty by the International Criminal Court into the widespread killings of suspects during an anti-drug crackdown under former President Rodrigo Duterte would be “totally unacceptable.”

Justice Secretary Jesus Crispin Remulla spoke in reaction to a decision on Thursday by judges in The Hague-based court allowing Prosecutor Karim Khan to resume an investigation that was suspended in late 2021 after the Duterte government said it was already looking into the killings and argued that the ICC, a court of last resort, did not have jurisdiction.

The ICC decision was welcomed by human rights groups and by relatives of mostly poor suspects killed in Duterte's police-enforced crackdown.

“The various domestic initiatives and proceedings, assessed collectively, do not amount to tangible, concrete and progressive investigative steps in a way that would sufficiently mirror the court’s investigation,” a panel of ICC judges said in their ruling Thursday after examining information from the Philippine government and Khan, and weighing comments from victims.

Remulla rejected any ICC investigation that violates the country’s sovereignty and the independence of its judicial system.

“We are a fully functioning judicial system and I don’t see where they will come in, what role they will play, unless they want to take over our legal system or they want to take over our country,” Remulla said at a news conference. “I don’t see that happening.”

The government is willing to talk with ICC investigators and provide details of the Philippine investigation into the drug deaths, “but to impose themselves on us, that’s totally unacceptable,” Remulla said, without elaborating.

He said the government investigation into the killings has taken a long time because of the difficulty of gathering evidence and other problems.

Randy delos Santos, whose 17-year-old nephew, Kian delos Santos, was shot to death by police in an anti-drug raid in August 2017, said the ICC decision revived hopes among still-grieving families that they could get justice and that powerful people behind the deaths could be held accountable.

Many more relatives of slain suspects are willing to talk now and possibly testify before the ICC after the end of Duterte's six-year term last year, he said.

“If they were afraid to talk before, they are now ready to relate what they know about the killings,” delos Santos, who now works for a Catholic church charity that helps families of slain suspects, said by telephone.

In a rare conviction, a Philippine court found three policemen guilty of involvement in Kian delos Santos's death in a slum in suburban Caloocan city after rejecting their claim that he opened fire at them with a pistol, prompting them to fire back. A security camera and witness accounts indicated that the teenager was dragged into a dark alley and shot to death as he pleaded for his life.

“The ICC investigation in the Philippines is the only credible avenue for justice for the victims and their families of Duterte’s murderous ‘war on drugs,’” said Phil Robertson, deputy Asia director of the group Human Rights Watch. “The ICC offers a path forward to fill the accountability vacuum.”

The killings being investigated by the ICC took place from Nov. 1, 2011, to March 16, 2019, in southern Davao city where Duterte was mayor, and later across the Philippines after Duterte became president.

Duterte and his top police officials have denied that they authorized law enforcers to conduct extrajudicial killings under the crackdown and said most of the victims were killed after violently resisting arrest. Duterte, however, openly threatened drug dealers with death during his presidency.

In 2019, Duterte withdrew the Philippines from the ICC after the court launched a preliminary examination into the killings. Critics said then that Duterte wanted to evade accountability. The ICC prosecutor, however, said the court continues to have jurisdiction over alleged crimes while the Philippines was a member of the court.

President Ferdinand Marcos Jr., who succeeded Duterte, has said he has no plan to bring the Philippines back into the ICC.