At least 20 people were killed and dozens wounded on January 27 in two bomb blasts at a Catholic Cathedral in Jolo, an island in southern Philippines.

Abu Sayyaf, an Islamic militant group, and other armed fighters are active in the island.

Police said at least 77 people were wounded in Sunday’s incident.

The number of fatalities was revised after police said earlier that 27 people were killed.

The first bomb went off in or near the cathedral of Jolo, the capital of Sulu province, followed by a second blast outside the compound as government forces were responding to the attack, security officials said.

The initial explosion scattered the wooden pews inside the Cathedral of Our Lady of Mount Carmel and blasted window glass panels, and the second bomb hurled human remains and debris across a town square fronting the church, witnesses said.

Pope Francis has denounced the bombing of the Cathedral of Our Lady of Mount Carmel in Jolo, Philippines. Two bombs blasted the cathedral during Sunday Mass, killing 22 people and wounding 111 more.

Entrusting the victims, who included five army soldiers, to Jesus and Mary, the Pope reiterated “my strongest condemnation for this episode of violence that once again strikes this Christian community.”

President Rodrigo Duterte’s spokesman Salvador Panelo condemned the “act of terrorism” and vowed that government forces will pursue the perpetrators of the attack.

“The Armed Forces of the Philippines will rise to the challenge and crush these godless criminals,” he said.