Philippine President Rodrigo Duterte may be surrounded by a fresh controversy after a former militiaman testified against him Thursday in front of the country’s Senate, saying the former Davao City mayor ordered the killings of almost 1,000 criminals and political opponents, as well as the bombing of a mosque in 1993.

The ongoing Senate hearing was called to assess Duterte’s anti-drug campaign that has left over 3,000 suspected drug users and dealers dead in the past few months, since Duterte assumed presidency at the end of June. The committee inquiry has been led by Senator Leila de Lima — who the president has accused of being indirectly involved in the drug trade.

Edgar Matobato, who claims to have been a member of the infamous “Davao Death Squad (DDS),” was presented by de Lima at the Senate and he told the house he heard Duterte order some of the killings himself.

In 1988, Matobato — who was a member of the Cafgu (Citizen Armed Force Geographical Unit) — was recruited by Duterte, who was then mayor of Davao city, to join a vigilante group that later became the DDS. According to Matobato, more members — including rebel returnees and policemen — joined them in 1993.

“Our job was to kill criminals like drug pushers, rapists, snatchers,” Matobato said under oath, explaining his role as a member of the squad.

Following the 1993 bombing of the Davao Cathedral, Duterte issued the order to kill Muslims by bombing the Bangkerohan Mosque, Matobato said. He explained that Duterte himself came to their office to give the order and Matobato was the one who hurled the grenade at the mosque. However, no one was killed in the explosion.

In another instance, Matobato said his group kidnapped and killed a man named Salik Makdum in 2002, on Duterte’s orders, local news networks reported. According to Matobato’s testimony, the current chief of the Philippine National Police (PNP) Ronald dela Rosa, who was then the chief of Davao City’s Presidential Anti-Organized Crime Task Force, knew of the operation. Dela Rosa was present at the Senate hearing Thursday.

“They were killed like chickens,” Matobato said of the people he and his group killed.

While the president himself has not responded to these allegations yet, his spokesman Martin Andanar said there was a lack of evidence in the government investigations into Duterte’s time as mayor of Davao and rejected the claims in their entirety.

The Guardian reported that Matobato entered a witness-protection program after the guilt of the executions overwhelmed him but left the program after Duterte became president as he feared for his life.