President Rodrigo Duterte said on Wednesday he has "been demonized" amid allegations of extrajudicial killings in the country due to his war against illegal drugs.

Duterte made the statement in front of the jurists and lawyers from Southeast Asia as he explained to them why he has to be tough against narcotics.

"I know that I have been demonized. And well, of course, I will assure you upon my oath as a lawyer and before God that some are true, some are not," he said in about an hour speech at the Commemorative Session and Concert Program ASEAN Law Association Governing Council in Malacanang.

He denied he was the one who ordered summary executions of drug suspects.

"And the extrajudicial tag that has been placed on me is simply not true. I have been a prosecutor for almost eight years doing trial work almost everyday to earn my keep before I became mayor," he said.

He blamed "politics and fake news" why his administration was being accused of engaging in extrajudicial killings.

Some groups here and abroad have been criticizing Duterte due to extrajudicial killings.

Duterte said there were minors who got involved into illegal drugs because they were being used by the drug syndicates and yet they were not imprisoned.

Under the Philippine law, minors are not jailed unless they are above 15 years old but below 18 years old who acted with discernment.

Duterte also explained why most of the poor got killed in the anti-drug operations.

This is because "the market of shabu is the poor people," he said.

In the same speech, Duterte warned Iloilo City Mayor Jed Patrick Mabilog that he would be the next target of his anti-drug campaign.

"The mayor of Iloilo City, I identified him, I said, 'You're next, you're next'," he said after he mentioned the deaths of Albuera, Leyte Mayor Rolando Espinosa and Ozamiz City Mayor Reynaldo Parojinog in the hands of the policemen.

Mabilog went on leave as mayor of Iloilo as he traveled abroad. Celerina Monte/DMS