President Rodrigo Duterte has warned of doing something "drastic" in the coming days in the wake of killings in Negros Oriental.

"I will explain in the coming days. But I'm about to do something drastic," said Duterte in a speech Thursday night at the 28th founding anniversary of the Bureau of Fire Protection in Pasay City.

"It will not sit well with everybody, maybe including you, but it is needed," Duterte added.

He noted that in some parts of the Philippines, "everything is not going well."

He said he was talking about Negros where the killing "has not stopped. It has gone unabated, unbridled, unstoppable."

Duterte said many barangay captains have been killed as he blamed the communist New People's Army for the violence.

"To the NPA, I'm warning you. This cannot go on," he said.

Duterte said even firemen should be armed so they could help in maintaining peace and order.

"But you must help. And you must help kill. Kill the enemy. Because your enemy will really kill you. So I'm warning everybody, including the Sparrows, the angels, I called them my Sparrows, will also looking for you...the angels of the government," he said.

At least 21 people were reported killed in Negros Oriental since July 18, when four policemen were shot dead and allegedly tortured by the Maoist rebels.

While he plans to do something drastic, Duterte reiterated he has no ambition of becoming a dictator.

He again said he should be shot dead if he overstays in Malacanang.

"I do not need it. I am tired. I want to rest. I just want to complete what I agreed with the people as the term of my mandate. That's all," he said.

Presidential Spokesperson Salvador Panelo earlier said Duterte might declare martial law in Negros Oriental if the military and the local government officials would propose it. Celerina Monte/DMS