Terrorists detonated a bomb outside Cotabato Cathedral in the southern Philippines while Mass was taking place on Sunday, injuring 22 people.

Among those injured were 12 soldiers charged with patrolling the church, one of the security measures adopted during the Christmas holidays in a region marked by Islamist violence.

“We do not discount the possibility that Bangsamoro Islamic Freedom Fighters (BIFF) and Daesh-inspired groups are behind this,” said regional military spokesperson Major Arvin Encinas, referring to a militant jihadist group affiliated with the Islamic State.

“It is a cowardly act on the eve of the Christmas celebrations,” said Father Zaldy Robles, a priest serving at the Cathedral. “The Church strongly condemns these attacks on people and churches.”

Father Robles told the Fides Catholic news agency that the explosion occurred while Sunday Mass was underway, after which a number of terrified people sought refuge in the church building.

For their part, local Church leaders have urged the local population not to be cowed by the terror threats but to “celebrate Christmas with joy and courage.”

Just ten days ago, militants with ties to the Islamic State set off a bomb in a shopping mall in Cotabato in the heart of Christmas shopping season, killing two people and wounding another 35.

In a similar incident last January, two bombs were detonated during Sunday Mass at the cathedral on nearby Jolo Island, an area considered a stronghold of Islamist militants. The blasts killed 27 people and injured 777 more.

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