A government soldier takes up position during a patrol along a deserted street in Marawi City, southern Philippines, on May 27, 2017.

:: Philippine fighter aircraft unleashed rocket fire against militants on Saturday, prompting villagers to hoist white flags to avoid being targeted as the military turned to airstrikes to try to end the siege of a southern city by ISIS-allied militants.

The predominantly Muslim city of Marawi, home to some 200,000 people, has been under siege since a failed army raid on Tuesday on a suspected hideout of Isnilon Hapilon, who is on Washington’s list of most-wanted terrorists.

Hapilon got away and fighters loyal to him took over parts of the city, burning buildings, taking cover in houses and seizing about a dozen hostages, including a Catholic priest. Their condition remains unknown.

At least 48 people have died in the fighting, including 35 militants and 11 soldiers, officials say, adding that an unspecified number of civilians are feared to have died.

Many trapped

While up to 90 percent of Marawi’s people have fled amid the fighting, many who were trapped or refused to leave their homes have impeded military assaults, officials said. That has slowed efforts to end the most serious crisis President Rodrigo Duterte has faced since he took power nearly a year ago.

“In as much as we would like to avoid collateral damage, these rebels are forcing the hand of government by hiding and holding out inside private homes, government buildings and other facilities,” the military said in a statement.

“Their refusal to surrender is holding the city captive,” it said. “Hence, it is now increasingly becoming necessary to use more surgical airstrikes to clear the city and to bring this rebellion to a quicker end.”

The violence prompted Duterte on Tuesday to declare 60 days of martial law in the southern Philippines, where a Muslim separatist rebellion has raged for decades. But the recent violence has raised fears that extremism could be growing as smaller militant groups unify and align themselves with the ISIS.

ISIS funding

Hapilon’s group has received a “couple of million dollars” from the ISIS, Defense Secretary Delfin Lorenzana told reporters without elaborating on Friday.

As air force planes and rocket-firing helicopters pounded militant positions on Saturday, fleeing residents waved white flags or hoisted them on their roofs to signify that they are not combatants.

“I saw two jets swoop down and fire at rebel positions repeatedly,” Alexander Mangundatu, a security guard, told The Associated Press in Marawi as a plume of black smoke billowed from a distant commercial area that was hit. “I pity the civilians and the women who were near the targeted area. They’re getting caught in the conflict and I hope this ends soon.”

Military spokesman Brig. Gen. Restituto Padilla said government forces are working to “clear the city of all remnants of this group.”

Some civilians refused to evacuate because they want to guard their homes, slowing down the government operations, he said.

“But that’s fine as long as civilians are not hurt,” Padilla said.

On Friday, Duterte ordered his troops to crush the militants, warning that the country is at a grave risk of “contamination” by the ISIS.

Duterte told soldiers in Iligan, a city near Marawi, that he had long feared that “contamination by ISIS” loomed in the country’s future.

“You can say that ISIS is here already,” he said.