Government forces killed 15 of the rebels and rescued six hostages in fighting that began Thursday and lasted into early Friday, Armed Forces spokesman Lt. Col. Ramon Zagala said.
The freed hostages told troops they believe no one else is being held by the separatist group, the Moro National Liberation Front, which took 180 people hostage in the coastal city of Zamboanga more than two weeks ago.
Efforts to negotiate the hostages' release failed, resulting in intense bursts of fighting that had left 158 people dead as of Thursday, including 125 members of the MNLF, the government-run Philippines News Agency said.Troops have captured 186 rebels and are now in a clearing operation to sweep the region of any remaining rebels, Zagala said.
"We have severely diminished the numbers of the faction, but we will not rest until we have cleared the area," he said.
The rebels are part of the MNLF, a separatist movement founded in 1971 by Nur Misuari with the aim of establishing an autonomous region for Muslims in the mainly Catholic Philippines.
The MNLF signed a peace deal with the central government in Manila in 1996, but some of its members have broken away to continue a violent campaign.
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