JOLO, Philippines – At least 27 people were killed when two bombs hit a Roman Catholic cathedral on a southern Philippine island, the military said Sunday.

Security officials say the first bomb went off in or near the Jolo cathedral in Sulu province during a Sunday Mass, followed by a second blast outside the compound as government forces were responding to the attack.

Five soldiers and a member of the coast guard were among the dead while 77 others were wounded.

President Rodrigo Duterte’s spokesman condemned the incident as an “act of terrorism and murder”.

“We will pursue to the ends of the earth the ruthless perpetrators behind this dastardly crime until every killer is brought to justice and put behind bars. The law will give them no mercy,” Salvador Panelo said in a statement.

Authorities said the notorious Abu Sayyaf kidnap-for-ransom group could be behind the blasts.

No one has immediately claimed responsibility.

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