Two suicide attackers carried out a double bombing in the southern Philippines that killed 14 people and wounded scores, the army chief said Tuesday, as he called for martial law to be imposed.

Monday's attacks -- the country's deadliest this year -- happened on Jolo island in Muslim-majority Sulu province where government-backed security forces have long been fighting the Islamic State-linked Abu Sayyaf militant group.

The first blast -- initially thought to have been an improvised explosive device attached to a motorbike -- was followed an hour later by a suicide bomber detonating her explosives.

Eight members of the security forces and six civilians were killed in the apparently coordinated blasts.

Among the 75 wounded were 48 civilians, 21 soldiers and six police.

Military personnel and civilians stretcher away a soldier after the bombs in Jolo
Military personnel and civilians stretcher away a soldier after the bombs in Jolo AFP / Nickee BUTLANGAN

Lieutenant General Cirilito Sobejana said witness testimony and CCTV footage showed the first bomb had been detonated by a suicide attacker.

"It has been validated," Sobejana told reporters.

No one has claimed responsibility for the attacks, but Lieutenant Colonel Ronaldo Mateo said Monday that Abu Sayyaf was "most probably" behind the bombing.

Sobejana said martial law should be imposed "to bring back normality and for us to really control the movement of people".

Listed by the United States as a terrorist organisation, Abu Sayyaf is a loose network of Islamic militants blamed for the Philippines' worst terror attacks as well as kidnappings of foreign tourists and Christian missionaries.

Monday's explosions happened near a Catholic cathedral in Jolo where two suicide bombers blew themselves up in January 2019 killing 21 people. It was blamed on a group linked to Abu Sayyaf.