MANILA- Authorities on Tuesday issued conflicting claims on perpetrators of the double bomb attack on a church in Jolo, Sulu that claimed at least 21 lives.

President Rodrigo Duterte said suicide bombers were responsible for the blasts, noting that the perpetrators were a couple.

The military however has ruled out the possibility of a suicide bomber after two wounded victims revealed that a woman hid the bomb in a bag and left it in one of the pews inside the cathedral.

It was after the woman left the bag that the first explosion happened, Armed Forces of the Philippines Public Affairs chief Col. Noel Detoyato said.

“Ang method of deployment ng IED (improvised explosive device), iniwan yung bag, then babae, and then it was remotely detonated so that will dispel report na may suicide bombing,” Detoyato said.

(The bomb was deployed by a woman by leaving it inside a bag. It was remotely detonated so that will dispel reports that it was a suicide bombing.)

Earlier, the military released surveillance footage of a man, supposedly Alias Kamah, brother of slain bandit leader Surakah Ingog, triggering the explosive device.

Kamah, a known bomb maker, ran away from the church and out of the video's frame with several cohorts, moments after the explosion, said Col. Gerry Besana, spokesperson of the military's Western Mindanao Command.

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Defense Chief Delfin Lorenzana meanwhile echoed the military's claim on the first bomb attack, relying on eyewitness accounts as well.

"The first bomb that exploded inside the church was apparently left behind by a certain woman. This is according to hazy recollection a survivor sitting 4 pews behind the explosion," he said in a statement.

Lorenzana, however, noted that the second bomb that went off outside the church in Jolo was likely caused by a suicide bomber.

"The second bomb that exploded at the entrance about a minute and a half after may have been a suicide bomber as indicated by body parts strewn all over including half a face and neck and two feet," he said.

"It is more likely that the second bomb was caused by a suicide bomber," he added.

The suicide bomber, however, has yet to be identified, Lorenzana said.

Sunday's double bomb attack left at least 21 people dead and over 100 others injured.

The military is eyeing local terror group Abu Sayyaf as the perpetrator even as the Islamic State claimed responsibility for the attack.