SPO3 Arthur Lascañas has appeared in a press conference at the Senate.
He was accompanied by lawyers from the Free Legal Assistance Group (FLAG).
Lascañas was previously tagged by self-confessed hitman Edgar Matobato as the team leader of the so-called Davao Death Squad (DDS).
During the press conference on Monday morning, Lascañas claimed that when President Rudy Duterte was Davao City mayor, he had ordered the killings of some persons.
He said he had witnessed the shooting of an entire family from General Santos City.
This was supposedly following a kidnapping of a woman in Davao City.
Lascañas said they would receive P 50,000 to P 100,000 as reward, depending on the social status of the person they killed.
He also claimed that Duterte had ordered the bombing of Camamara mosque.
This was supposedly to retaliate for the bombing of Davao Cathedral.
Lascañas said his team was composed of members of the PNP anti-crime group with the help of rebel returnees.
Lascañas also claimed Duterte had ordered the murder of Davao-based radio commentator Jun Porras Pala in 2003.
Lascañas said Duterte had given them P 3 million for having killed Pala.
The money was divided among them.
Then Duterte had allegedly given him an additional P 1 million as reward.
Lascañas admitted that he was among those who killed Pala.
The press conference was called by Senator Antonio Trillanes.
Lascañas also said he had killed two of his brothers, Cecilio and Fernando, after they committed some crimes.
He also cited his blind loyalty to Duterte as reason why he had killed his brothers.
He shed tears during the press briefing.