MANILA, April 4 (Xinhua) -- At least four terrorists were killed and 13 people were wounded in Wednesday's fighting between the government security forces and a local terrorist group in southern Philippines, a military general said on Thursday.

Major General Cirilito Sobejana, commander of the Philippine Army's 6th Infantry Division based in Mindanao, said the clashes occurred early on Wednesday morning and Wednesday afternoon in a village in Maguindanao province of southern Philippines.

He said artillery rounds were delivered by the Philippine Army toward the position of about 60 alleged members of the Bangsamoro Islamic Freedom Fighters (BIFF) men on Wednesday morning and an airstrike followed.

Three BIFF members died in the initial fighting, the military official added.

Sobejana said, on Wednesday afternoon about 100 BIFF members came in as reinforcement, leading to another firefight that led to the death of another BIFF member and wounding of 11 other terrorists.

Two soldiers were also injured in the fighting.

Sobejana said government troops also recovered improvised explosive materials from the BIFF hideouts.

Simultaneous law enforcement operations conducted by government security forces in Mindanao since the first half of March have displaced more than 50,000 villagers, mostly farmers and fisherfolk, according to the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) in the Philippines.

The BIFF, an Islamic separatist organization based in southern Philippines, was founded in 2010 and accused of orchestrating multiple terrorist attacks.