MANILA (AFP) - The Philippines' police chief has called on drug users to kill traffickers and burn their homes, as he seeks to maintain momentum in President Rodrigo Duterte's controversial crime war that has claimed 2,000 lives.

"Why don't you give them a visit, pour gasoline on their homes and set these on fire to register your anger," Mr Ronald dela Rosa said in a speech aired on television on Friday (Aug 26). "They're all enjoying your money, money that destroyed your brain. You know who the drug lords are. Would you like to kill them? Go ahead. Killing them is allowed because you are the victim."

Mr Dela Rosa was speaking on Thursday to several hundred drug users who had surrendered in the central Philippines.

When asked if Mr Duterte supported Mr dela Rosa's call to murder and commit arson, presidential spokesman Ernesto Abella denied that was the police chief's intent.

"There is no such call. It's a passionate statement," Mr Abella told reporters on Friday, without elaborating.

Mr dela Rosa's comments followed Mr Duterte's own controversial directives that have sparked criticism from the United Nations and human rights groups.

Mr Duterte, 71, won May elections in a landslide on a promise to kill tens of thousands of suspected criminals in an unprecedented blitz that would eliminate illegal drugs in six months.

When he took office on June 30, Mr Duterte told a crowd in Manila: "If you know of any addicts, go ahead and kill them yourself as getting their parents to do it would be too painful."

Days after his election win, Mr Duterte also offered security officials bounties for the bodies of drug dealers.

The United Nations special rapporteur on extrajudicial killings, Ms Agnes Callamard, said such directives "amount to incitement to violence and killing, a crime under international law".

However, Mr dela Rosa and Mr Duterte have insisted they are working within the law, while their aides have dismissed some of their comments as "hyperbole" meant to scare drug traffickers.

Nevertheless, Mr dela Rosa told a Senate inquiry this week that the confirmed number of people to have died in the drug war was 1,946.

He said the police had shot dead 756 suspects in self defence.

He said there were another 1,190 killings under investigation, but said they were likely due to drug gangs murdering people who could implicate them, as he hailed the success so far in the crime war.

"I admit many are dying but our campaign, now, we have the momentum," he told the Senate.