The Philippine government has warned Muslim rebels who have been holding more than 100 people hostage in a southern port city to peacefully end the four-day standoff "at the soonest possible time," saying it is ready to use force.
It was the toughest talk by President Benigno Aquino III's administration since Moro National Liberation Front guerrillas occupied coastal communities and took scores of residents hostage in Zamboanga city.
Presidential spokesman Edwin Lacierda said any attempts by other groups to sow trouble would be crushed, citing the army's defeat of an extremist group's attempt to set a nearby village and wharf on fire.
"While the government is exhausting all avenues for a peaceful resolution to the situation, let it be clear to those defying us that they should not entertain the illusion that the state will hesitate to use its forces," Mr Lacierda said. "It is time for you to co-operate to resolve this situation peacefully at the soonest possible time," he said.
The most serious security crisis to hit Mr Aquino's administration began on Monday when about 200 armed Moro rebels, who have been overshadowed by a rival group in talks with the government for a new Muslim autonomy deal, clashed with government troops who had foiled their plan to march through Zamboanga city and hoist their flag at city hall.
They then stormed into five coastal villages and seized scores of residents to use as human shields as hundreds of elite army troops and police, backed by tanks, helicopters and navy gunboats, surrounded them.
Government forces engaged the rebels in a daylong exchange of gunfire on Thursday in Santa Catalina village, where the insurgents were holding some of their hostages. The fierce clash ignited a blaze that destroyed about 30 houses. Two Huey helicopters hovered as dark smoke billowed from the rebel-held coastal community.
As the fighting raged in Zamboanga, a separate group of about 150 insurgents led by the al Qaida-linked Abu Sayyaf attempted to set fire to a village and a wharf on the rural outskirts of predominantly Christian Lamitan city on nearby Basilan island. The attack was repulsed by government forces in an hour-long clash that left a government militiaman and an unspecified number of militants dead, and two soldiers wounded.
Another government militiaman was missing and troops were pursuing the attackers.