Philippines: Four killed after explosion rocks Sunday mass service

The blast took place in Marawi on the southern island of Mindanao, according to CNN affiliate CNN Philippines.

According to reports, a section of the seating area was blown up following the blast.

Philippine President Ferdinand Marcos Jr. condemned the incident and wrote on X: "I condemn in the strongest possible terms the senseless and most heinous acts perpetrated by foreign terrorists upon the Mindanao State University (MSU) and Marawi communities early this Sunday morning. Extremists who wield violence against the innocent will always be regarded as enemies to our society."

"I extend my most heartfelt condolences to the victims, their loved ones, and the communities that have been the target of this latest assault on peace," he said.

"I have instructed the Philippine National Police (PNP) and the Armed Forces of the Philippines (AFP) to ensure the protection and safety of civilians and the security of affected and vulnerable communities. Additional security personnel are also being deployed," he said.

  In 2017, Marawi was the scene of a five-month battle between government forces and militants with links to the Islamic State group, reported BBC.