ISIS has claimed responsibility for a deadly explosion that ripped through a Catholic mass service at a university gym in the southern Philippines on Sunday.
At least four people were killed and dozens of others were injured in the blast at the Mindanao State University in Marawi City, according to authorities.
In a communique, ISIS said its fighters “detonated an explosive device on a large gathering of Christian disbelievers in Marawi City,” according to the SITE Intelligence Group, a counterterrorism threat intelligence organization that tracks the online activity of extremist groups.
Photos of the scene showed soldiers and emergency workers standing among debris in the gym. A section of the seating area was blown up, chairs strewn across the floor.
Lanao del Sur province Gov. Mamintal Adiong Jr., told reporters more than 40 people were being treated at a government hospital in Marawi, while a number of others with minor injuries were treated at the university’s infirmary following the blast.
Philippine President Ferdinand Marcos Jr. condemned the attack in a post on X, formerly Twitter. Without naming any specific groups or elaborating further, he described the blast as “senseless and most heinous, perpetrated by foreign terrorists.”
“Extremists who wield violence against the innocent will always be regarded as enemies to our society,” he said, adding that additional security personnel had been deployed to assist in the response.
The United States condemned the “horrific terrorist attack” in a government statement.
“The United States is in close contact with our Philippine partners and stands with the people of the Philippines in rejecting this act of violence,” State Department Spokesperson Matthew Miller said.
Mindanao, the second largest island in the Philippines, is home to several Islamist insurgent groups and has long been a hotbed of insurgency against the Philippine government.
While the Philippines is mostly Catholic, Mindanao is home to a sizable Muslim population.
In 2017, ISIS-affiliated militants laid siege to Marawi for five months. The violence forced more than 350,000 residents to flee the city and the surrounding areas before Philippine forces liberated the city.
This story has been updated with additional developments.