MANILA, Aug. 23 (Xinhua) -- One Abu Sayyaf militant was killed and at least 20 government soldiers wounded when Philippine troops clashed on Thursday with some 40 militants in southern Philippine Sulu province, a military spokesman said.

Lt. Col. Gerry Besana of the military's Western Mindanao Command said the heavy fighting that broke out around 9 a.m. local time in Langhub village of Patikul town, an Abu Sayyaf stronghold in the remote jungles, lasted almost an hour.

He said the injured soldiers were hit by shrapnel from rifle grenades.

This is the third clash this week. Besana said clashes also broke out in nearby villages of Tugas and Latih and in Patikul town earlier this week.

The military continues its operation to pursue the militants, Besana said.

Abu Sayyaf, a radical Islamist groups in the Philippines, often carries out kidnappings, bombings and beheadings in western Mindanao, particularly in their lair in the island provinces of Basilan and Sulu.