Three other soldiers were wounded and an undetermined number of Abu Sayyaf members wounded or killed in the fighting Thursday on tiny Pilas island, military Southern Command chief Maj. Gen. Roy Kyamco said.
He said OV-10 planes had attacked positions of the Abu Sayyaf in Pilas after it was learned that more than 100 Abu Sayyaf fighters and those allied with the group had landed there from Jolo island.
The gunmen headed to Pilas in an attempt to reach the larger nearby island of Basilan, said local Army chief Col. Bonifacio Ramos.
The Abu Sayyaf has been linked by both Washington and Manila to the al-Qaeda terror network of Saudi dissident Osama bin Laden.
The group, led by Abu Sayyaf chieftains Khadaffy Janjalani and Isnilon Hapilon, are believed to have fled Jolo to escape a planned US-Philippine joint military operation there in the coming months, Ramos said.
Navy boats are on patrol to keep the Abu Sayyaf members from slipping out of Pilas while military forces on Basilan have been put on alert to prevent the rebel leaders and their followers from landing there, the colonel added.
The US government last year offered as much as $5 million for information leading to the capture of Janjalani, Hapilon and other Abu Sayyaf leaders, who had killed two US hostages.
In Jolo, government forces on Thursday attacked Abu Sayyaf positions in the town of Patikul, leading to an undetermined number of rebel casualties, the islands Army chief said.
"We got radio intercepts, saying many rebels are killed and injured," said Colonel Alexander Aleo, adding his forces were stepping up their effort to recover two female Christian preachers still in the hands of the Abu Sayyaf.
The two preachers were among six Jehovahs Witnesses abducted by the Abu Sayyaf in August last year. Two others were beheaded and the other two escaped last month. With Roel Pareño, Mike Frialde