President Rodrigo Duterte's allies in the Senate yesterday ousted the head of a committee probing his anti-crime drive, which has left thousands dead in less than three months. Sixteen of the 24 senators voted to remove Senator Leila de Lima as chairman of the committee on justice and human rights.

Ms de Lima, 57, accused Mr Duterte of orchestrating her ouster.

Her removal comes days after she presented as a witness a self-confessed hitman who linked the President to over 1,000 murders when Mr Duterte was mayor of Davao city from 1988 to 2013.

Mr Edgar Matobato, 57, described how he and six other men, supposedly on Mr Duterte's orders to kill criminals, strangled and disembowelled suspects, hacked them to pieces and torched them, and dumped their bodies at sea. He said one of their victims was fed alive to a crocodile.

Mr Duterte's allies have called Mr Matobato a "perjured" witness who offered nothing but "lies and fabrications".

Ms de Lima was unseated as the House of Representatives prepared to hold hearings on separate allegations she received pay-offs from drug kingpins serving time in the national penitentiary.

Justice Minister Vitaliano Aguirre told reporters he will present dozens of high-profile inmates who will testify that they raised millions of pesos to bankroll Ms de Lima's Senate bid.

The inmates, in turn, received privileges that allowed them to continue their drug trade while behind bars, said Mr Aguirre, 69.

Ms de Lima had been leading a Senate inquiry into the deaths of more than 3,000 drug suspects killed by either police or vigilantes since Mr Duterte took office on June 30.

In a speech yesterday, Senator Alan Cayetano, 45, who ran as Mr Duterte's running mate but lost in the recent elections, accused Ms de Lima of "destroying the integrity and reputation of the Senate… in her desire to destroy the President".

Afterwards, Senator Manny Pacquiao moved to unseat Ms de Lima as chair of the committee on justice and human rights.

Mr Pacquiao, 37, the eight-time boxing champion who ran for senator under former vice-president Jejomar Binay but has since switched loyalty to Mr Duterte, agreed with Mr Cayetano that Ms de Lima was "not fair to all".

The Senate then went on an executive session.

About an hour later, they voted to unseat Ms de Lima and replace her with Senator Richard Gordon.

Senate President Aquilino Pimentel, head of Mr Duterte's political party, told reporters: "The majority in the Senate believed that by reorganising we will have a more objective chairman."

The committee on justice and human rights was scheduled to resume questioning of Mr Matobato todaybut the hearing has been moved to Thursday.

Mr Pimentel, 52, said Mr Gordon, 71, would have to decide whether to continue the hearing and whether Mr Matobato would remain a witness.