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MANILA, April 10 (Xinhua) -- Eighteen government soldiers and five militants were killed following a firefight in Southern Philippines on Saturday, military said on Sunday.

The fierce gun-battle also resulted in the wounding of 53 other soldiers and 20 militants, said Maj. Filemon Tan, spokesman of the military's Western Mindanao Command.

The fighting broke out 7:55 am Saturday at the village of Baguindano, Tipo-tipo town in Basilan involving forces of the Army's 4th Special Forces Battalion and 44th Infantry Battalion against around 120 Abu Sayyaf militants.

He said the fighting lasted until around 5:30 p.m..

Lt. Col. Benedicto Manquiquis, spokesman of the Army's 1st Infantry Division, said the troops were on a combat operation when the fighting broke out.

Tan declined to give further details of the encounter, saying he is preparing a more detailed statement.

"Initially, I confirm that there was an encounter in barangay (Village) Baguindan, Tipo Tipo, Basilan with the results on government side: 18 KIA (killed in action) 53 WIA (wounded in action)," said Tan.

The 400-strong Abu Sayyaf Group, founded in the early 1990s by Islamic extremists, is a violent terrorist group operating in southern Philippines. The group is notorious for a series of kidnappings, bombings and beheadings over the decades.