One communist rebel was killed in a clash with government forces in Occidental Mindoro province Saturday, military officials said.

Troops from the 68th Infantry Battalion encountered New People’s Army (NPA) rebels on the outskirts of Monteclaro village in Rizal town around 6 a.m., leading to a 20-minute firefight, according to the Army’s 2nd Infantry Division.

The military recovered two M16 rifles, ammunition, two improvised explosive devices and documents after rebels retreated.

The slain fighter’s identity was not immediately released.

Maj. Gen. Cerilo Balaoro Jr., commander of the 2nd Infantry Division, urged remaining rebels to surrender and participate in the government’s reintegration program.

The Philippine communist insurgency, now in its 55th year, is one of Asia’s longest-running conflicts.

While notably weakened from its peak in the 1980s, the NPA continues to operate in remote areas of Mindoro and other parts of the country.

Mindoro has seen sporadic clashes between government forces and NPA fighters in recent years.

The mountainous terrain and rural poverty have made the island a persistent base for rebel operations, despite military gains in declaring some areas stable.

The Communist Party of the Philippines-New People’s Army emerged in 1969, wanting to overthrow the government through guerrilla warfare.

Peace talks have repeatedly collapsed, with the military pursuing both combat operations and surrender programs targeting an estimated few thousand remaining fighters nationwide.