Troops and communist rebels on Sunday clashed in Mindoro province, hours after President Rodrigo Duterte announced that he is suspending the government's peace talks with the Communist Party of the Philippines (CPP).
The military reported that one suspected New People's Army (NPA) member has been killed in the ongoing firefight.
The report said the firefight in an undisclosed area in Mindoro province started at 2 p.m.
Troops have recovered a .45 pistol.
Duterte on Saturday night said he is suspending peace talks with the communist group.
He said he would not heed the CPP's call for him to release all political detainees.
Duterte made the announcement after he lifted on Friday the government's unilateral ceasefire with the CPP. The communist group lifted its ceasefire declaration first.