JOLO, Philippines: A double bomb attack during services at a Roman Catholic cathedral killed at least 18 people on a southern Philippines island.
The attack in a stronghold of Islamist militants, including the ISIS loyalists Abu Sayyaf, came five days after voters backed expanded Muslim self-rule in the region.
A powerful first blast caused major damage and left bodies strewn inside the cathedral.
Just moments later a second explosion outside killed troops who were rushing to help.
It is one of the deadliest bomb attacks to strike the insurgency-plagued southern Philippines in years, and shows the insurgency in the region is still a threat despite recent steps toward peace, experts said.
The bombings came less than a week after voters' decisive approval of giving Muslims in the south more control over their own affairs, which sparked hopes of reducing long-time separatist violence.
Bishop Angelito Lampon, who previously served in Jolo, said Sunday's attack may be the worst, but was certainly not the first on the church.
"In my 20 years there from 1998 to last week, there were seven hand grenades thrown into our cathedral," he told AFP. "Fortunately there was just a little damage and no casualties."
Manila swiftly vowed to hunt down the attackers, but no group has claimed the bombing.
Five soldiers, a member of the coast guard and 12 civilians were among the dead while 83 other people were wounded, said regional military spokesman Lieutenant Colonel Gerry Besana.
The second bomb was left in a motorcycle in the parking area outside the church, a military report said.
Authorities said the notorious Abu Sayyaf group could be behind the blasts.
