MANILA: More than 24,000 people fled their homes as the Philippine military used airstrikes and artillery against Muslim extremists who have pledged allegiance to the Islamic State, authorities said Thursday.

Almost a week of attacks on members of the Bangsamoro Islamic Freedom Fighters (BIFF) in the strife-torn southern island of Mindanao has displaced residents of six towns, said Jofelle Delicana, spokeswoman for the civil defence office.

About 24,300 villagers were forced to take refuge in schools, makeshift tents or with relatives after the military launched their assault on May 5, she told AFP.

Local army spokesman Captain Arvin Encinas said that reports from civilians and intelligence sources indicate that as many as 31 BIFF guerrillas have been killed including the group’s leader, Commander Ismael Abubakar, also known as “Bungos”, as well as two of his aides.

“We believe they are among the dead considering our information that they were there in the location hit by airstrikes,” he told AFP.

He said however that no bodies had been recovered and that the death toll could not be verified.

Seven soldiers have been slightly wounded in the fighting, he added.

“We used all available air assets and artillery assets and armour,” the captain said, declining to give details.

Six Indonesians from the Islamic State group who were training the BIFF in bomb-making were part of the remnants of the group that is being surrounded by the army, he added.

“Our assessment is they have less space to move while we are conducting our airstrikes because all our available troops have been deployed,” Encinas said.

The group of almost 100 BIFF were targeted after they were involved in the planting of make-shift bombs and a number of murders in recent months.

The BIFF split from main Muslim rebel group the Moro Islamic Liberation Front (MILF) in 2008 after the MILF opened a peace process with the government.

Since then, its leaders have been seen in videos pledging allegiance to the IS movement that has taken control of vast swathes of the Middle East.

Encinas said Bungos had been trying to forge closer connections with IS so he could get more overseas assistance.

While the Philippines is largely Catholic, the southern third is home to a sizable Muslim minority and extremist groups and guerrillas like the BIFF who are fighting for a separate Islamic state. -AFP