The Philippines' military chief says three Indonesians and a Malaysian are among 37 militants who were killed in an assault that captured the extremists' southern jungle camp.

Gen. Eduardo Ano says 14 of the dead have been identified so far from a series of clashes in southern Lanao del Sur province.

Officials said an army general raised the Philippine flag in the camp belonging to the Maute armed group, which is allied with Islamic State militants, a few hours after troops seized it on Monday.

Ano says mopping-up operations are ongoing and troops are trying to locate Filipino militant leader Isnilon Hapilon.