MANILA - Senators abruptly ended an inquiry into claims that the alleged Davao Death Squad operated under President Duterte because they were afraid of earning the tough-talking leader's wrath, Senator Antonio Trillanes IV claimed Tuesday.

Retired policeman Arturo Lascañas on Monday told senators that he personally killed about 200 people as a member of the DDS allegedly at the behest of Duterte. He also admitted to lying about the DDS during an October legislative probe because police had warned him to "deny everything".

The senators, several of whom are Duterte supporters, challenged Lascañas' credibility for recanting his earlier statement. The head of the investigation, Senator Panfilo Lacson also said there was no point of pursuing the probe because Lascañas failed to present independent evidence.

Trillanes, however, said lawmakers only shut down the inquiry to keep the favor of the President.

"Ang implication kasi, mamamatay-tao si Presidente. Ayaw nilang harapin iyun kasi hindi nila alam ang gagawin. Hindi nila kayang sabihin iyun dahil nga baka balingan sila ng galit ni President Duterte," he told radio DZMM.

(The implication is that our President is a murderer. Senators do not want to face that because they do not know what to do as they might earn the anger of President Duterte.)

Lawmakers, he added, failed to find holes in Lascañas' testimony during their 6-hour grilling so they resorted to challenging his credibility instead.

Trillanes also swatted aside speculations that the self-tagged DDS leader only surfaced due to a personal grudge.

"Napakababaw ng gusto nilang mangyari. Kaya raw lumalabas ngayon kasi ni-reject daw ang kanyang mga kabuhayan. Tingnan niyo naman iyan, Presidente ang itinuturo niya... Aakusahan niya ngayon na involved sa murder. Subukan nga nilang gawin iyun," he said.

"Sila nga, hindi nila kayang magsabi ng negatibo sa Presidente -- mga senador sila ha. Ang ginagawa nila ay sumipsip kay Presidente kasi ayaw nila mapagbalingan ng galit. Senador na sila noon ha, ito retiradong pulis, tinataya ang buhay pati pamilya."

(What they want to imply is too shallow. They say Lascañas only outed himself because he lost his livelihood. Look, he is implicating the President, accusing him of murder. They should try doing that. They're senators but they can't even say anything negative about the President. They flatter him because they do not want him to be angry at them. And here is a retired policeman risking his life and that of his family.)

• Lascañas denies getting paid to testify

Trillanes said senators, if they wanted, could seek evidence themselves and allow more witnesses to come forward.

He also slammed his fellow lawmakers for dismissing Lascañas' claims while readily accepting the testimony of drug convicts and witnesses who also failed to present evidence on the alleged involvement of Senator Leila De Lima in the narcotics trade.

"Ang pinaniniwalaan ng mga senador, iyung testimonya ng drug lord, yung si Kerwin Espinosa, sina [Ronnie ]Dayan," he said.

(What senators believe in are the testimonies of professed drug lord Kerwin Espinosa and De Lima's driver, Ronnie Dayan.)

• Govt has no 'ex-deal' with witnesses vs de Lima - Aguirre

Duterte, for his part, has denied ordering summary executions, either as president or during his 22 years as Davao mayor. His top police commander, Ronald dela Rosa, a former Davao police chief, calls the death squad "fiction" created by the media.

• Duterte: I did not give orders to kill specific persons

Human rights groups documented about 1,400 suspicious killings in Davao while Duterte was mayor and critics say the war on drugs he unleashed as president has the same hallmarks.

More than 8,000 people have been killed since Duterte took office eight months ago, mostly drug users killed by mysterious gunmen in incidents authorities attribute to vigilantes, gang members silencing informants, or unrelated murders.

• Cops abused power in Duterte's drug war: Human Rights Watch report

Police reject activists' allegations that they are behind most killings and say they are responsible for 2,555 of the deaths, when suspects had resisted arrest. -- With Reuters