Philippine President Rodrigo Duterte yesterday said human rights advocates who are pressing him to end the killings that have blighted his anti-crime push were too "timid".

But he remained mum on a self-confessed hitman's allegations linking him to "death squads".

"These timid human rights (advocates) tell me to build a case then file (in court)," Mr Duterte said in a speech at a military base. He showed a thick file that he said had the names of over a thousand governors, mayors, congressmen, generals, and low-level policemen and local officials with ties to the narcotics trade.

"Tell me how? They're too many; I can't kill them all. They may end up killing me," he said, adding that he might not last until the end of his six-year term.

Human rights advocates, including United States President Barack Obama and United Nations chief Ban Ki Moon, have criticised Mr Duterte's ongoing war on drugs, which had led to over 3,000 extrajudicial killings in a little over two months.

Mr Duterte has refused to back down, saying he felt Mr Obama disrespected him, and calling Mr Ban a "fool".

But he has yet to react to the testimony given last week at a Senate inquiry by Mr Edgar Matobato, 57, alleging that when Mr Duterte was mayor of Davao, he organised "death squads" in a campaign of terror to rid the city of both criminals and his opponents.

Mr Matobato claimed that he had been part of a small band of killers known as the "Lambada boys" responsible for over 1,000 murders in Davao, and that Mr Duterte himself finished off a government agent in 2007.

Raul Dancel