MANILA (BLOOMBERG, REUTERS) - At least eight people were killed and more than a dozen injured when soldiers clashed with Islamic State-inspired militants in southern Philippine province of Sulu.

A heavy firefight started on Saturday morning (Feb 2) and lasted for nearly two hours between members of a scout ranger battalion and at least 150 members of the Abu Sayyaf group headed by Hatib Hajan Sawadjaan in Patikul town in Sulu, Colonel Gerry Besana, spokesman of the Western Mindanao Command, said in a text message.

The encounter in Patikul lasted nearly two hours, Col Besana said, with five soldiers and 15 militants also wounded.

The deadly clash in Sulu comes nearly a week after Jan 27's deadly blasts that left 22 people dead in a Catholic church.

Interior Secretary Eduardo Ano said on Friday that two suicide bombers from Indonesia were behind last Sunday's explosions in Sulu that also injured about a hundred people, with the Abu Sayyaf acting as a guide.

CNN Philippines also quoted Mr Ano as saying the Indonesian couple wanted to set an example among Filipino militants, adding there are still some foreign terrorists in the country.

The Philippine military this week launched an airstrike against a splinter group from the Abu Sayyaf that it believed led the attack.

Defence Secretary Delfin Lorenzana earlier said a Yemeni couple may have been behind the blast. In nearby Maguindanao province, military operations have intensified in a terrorist lair, and bomber planes were used to destroy militants' bunkers.

The bombings came days after voters endorsed a new autonomous region intended to end decades of violence in the impoverished Muslim-majority area.

The Mindanao region, home to the provinces of Sulu and Maguindanao, has been under martial law since domestic and foreign fighters dressed in black outfits overran Marawi City in 2017 and clung on through five months of air strikes and street battles reminiscent of scenes in Syria and Iraq.