PHILIPPINES President Rodrigo Duterte blamed a blast at a boxing match on drug gangs yesterday, citing military sources who claim it was revenge for his government’s bloody assault on drug dealers and users.

Wednesday’s bombing, which injured 32 people, including at least 10 children, was triggered remotely by mobile phone, police say. A suspect has been arrested in connection with the attack in Hilongos, Leyte province.

The army says it has recovered an 81mm mortar cartridge and the phone used to detonate the bombs, which it described as “home-made.” It has a heavy presence in the region because it is a base for terrorists of the Abu Sayyaf group, who swear allegiance to Islamic State (Isis) and have killed numerous civilians in bombings.

Leyte province is also home to Maoist guerillas of the Communist Party of the Philippines, with whom Mr Duterte’s government is negotiating a peace deal after decades of conflict.

The Maoists are not suspected of involvement in the boxing-match bombing. “I would say it has nothing to do with the left or the communists,” the president announced, emphasising that the attack was linked to the drug trade.

Since taking office in June Mr Duterte has presided over the extrajudicial killing of at least 6,000 alleged drug dealers, mostly by police, although the president has repeatedly encouraged citizens to kill anyone they suspect of involvement in the trade. Hundreds have fallen victim to such lynchings.

He is widely accused of having commissioned extrajudicial killings while mayor of the city of Davao and has both admitted and denied doing so. Earlier this month he told businessmen that he had cruised the city on a motorbike looking for people to kill, and on Tuesday he also boasted that he had thrown people to their deaths from a helicopter — a claim a spokesman immediately passed off as an “urban legend.”

Yesterday Mr Duterte distanced himself from the claim, saying “if it is true, I will not admit it.”