MANILA — Six Philippine soldiers were killed and 23 others wounded, the military said on Tuesday, when a platoon checking on reports of an infiltration by communist rebels stepped on improvised bombs as they negotiated hilly terrain.

The troops had been sent in on Monday after civilians had complained of harassment by guerrillas with the New People’s Army outside Borongan City on Samar Island, which is in the central eastern part of the country.

Six improvised bombs planted by the insurgents exploded before the soldiers engaged in a firefight with them, the military said. The 30-minute gun battle that followed led to the death of one guerrilla, the military said.

The killings were a reminder of the stubborn insurgent threat in remote areas of the Philippines despite military campaigns aimed at eliminating the rebels.