MANILA, Philippines >> Fifteen communist guerrillas were killed in a clash with Philippine troops just south of Manila on the same day that the government closed the door on peace talks with the rebels, the military said today.

Heavy fighting erupted Tuesday night after combined police and military forces caught up with a unit of the communist New People’s Army near the town of Nasugbu, about 45 miles south of Manila, according to the military. Brig. Gen. Arnulfo Marcelo Burgos, commander of the local infantry brigade, said a ranking guerrilla leader was believed to have been killed.

Troops in the countryside have been building up their forces against the New People’s Army, the armed wing of the underground Communist Party of the Philippines, which has been engaged in on-and-off peace talks with the government.

Last year, President Rodrigo Duterte moved to start negotiations with the rebels soon after taking office. The Communist Party’s self-exiled founder, Jose Maria Sison, was once Duterte’s university professor, and Duterte had hoped to sign a peace deal before his six-year term ends in 2022.

But the rebels have demanded more and more concessions, including the release of jailed comrades. Last week, Duterte called off the talks and threatened to put the rebels on a terrorist watch list. The New People’s Army is already on a U.S. list of wanted terrorist organizations, but Manila has not officially designated it as such.

On Tuesday, Duterte’s spokesman, Harry Roque, said the president was stripping rebel leaders of immunity from arrest, which Duterte had earlier granted them in order to facilitate the talks. The leaders should surrender now “or face punitive actions,” Roque said.

“We have to shut the doors for now to any ongoing peace talks,” he said. “I am not in a position to say that the door will forever be shut.”

Roque said the president might consider reopening negotiations if the rebels showed “the requisite sincerity.”

Duterte’s decision to end the talks came after a rebel attack on the southern island of Mindanao that killed two civilians, including an infant girl. Three police officers and six civilians were wounded in that clash.

Maj. Gen. Rhoderick Parayno, commander of the army’s 2nd Infantry Division, said the rebel unit involved in the fighting Tuesday night had been on the run since September and was responsible for a series of attacks in the region. He said the clash was “in line with the president’s pronouncement that the NPA are terrorists.”

“Soldiers are more committed than ever to push harder and finally put an end to this insurgency,” Parayno said.

The Philippine communists have been fighting since 1969, making theirs one of the longest-running insurgencies in Asia. Thousands of combatants on both sides have been killed, along with many civilians. The military estimates that the rebels have more than 5,000 guerrilla fighters in dozens of hot spots across the country.

Earlier this week, Duterte threatened to shut down companies in the countryside that pay so-called revolutionary taxes demanded by the rebels.

“For those who cannot resist, then you better close up,” Duterte said, accusing mining companies in particular of a “dangerous tendency of capitulating” to rebel demands.

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