MANILA, Feb 12, 2024 (BSS/AFP) - The alleged mastermind of a bombing at a Catholic mass in the southern Philippines has died after a clash between members of a pro-Islamic State group and government troops, officials said Monday.

Four people were killed and dozens wounded in the December 3 attack on worshippers inside a university gym in Marawi, the country's largest Muslim city, that was later claimed by the Islamic State group.

Eight Dawlah Islamiyah militants were suspected of carrying out the attack on Mindanao island, army brigade commander Brigadier General Yegor Rey Barroquillo told AFP.

Five have been killed in manhunt operations, one has been detained and another two were still on the run, he said.

Among the dead was Khadafi Mimbesa, who went by the alias of "Engineer". The Armed Forces of the Philippines said in a statement that he was the "mastermind" behind the bombing.

Mimbesa was wounded in a shootout between army soldiers and militants hiding out at a mountain farm near the remote southern municipality of Piagapo in late January, Barroquillo told AFP.

Nine militants, including three suspects in the bombing, were killed in the fighting.

Mimbesa was wounded but escaped and died days later while being cared for by a supporter, Barroquillo said, citing intelligence reports.

In the statement, military chief General Romeo Brawner urged other members of the militant group to surrender and "avoid the same fate as your dead comrades".

Militant attacks on buses, Catholic churches and public markets have been a feature of decades-long unrest in the south.

Manila signed a peace pact with the nation's largest rebel group, the Moro Islamic Liberation Front, in 2014, ending their deadly armed rebellion.

But smaller bands of Muslim fighters opposed to the peace deal remain, including militants professing allegiance to the Islamic State group.