A suspected improvised bomb attack at a university campus in the Philippines has left 24 people wounded - many critically - including students and teachers.
It appeared a fire was set off deliberately in a school building housing security personnel at the state-run Cotabato Foundation College of Science and Technology, before the blast occurred on Sunday night, police said.
"The fire drew responders, including firemen, teachers, and students, and they were among the injured," explained Senior Inspector Rolly Oranza of the local police force in the troubled Mindanao region.
He said 17 of the wounded remained in a critical condition at the hospital.
Police said they believed the explosion was caused by an improvised explosive device, but bomb experts are still determining the exact details.
No group has claimed responsibility and police are still trying to determine the motive, Inspector Oranza said.
The school is in Arakan, a quiet farming community on the southern island of Mindanao, populated mostly by indigenous tribes. The region is gripped by a Muslim insurgency that has left more than 150,000 dead.
While Muslim rebels are not known to operate in Arakan, there has been violence between armed paramilitary groups fighting for control of the area.
Communist rebels are also known to have some presence in Arakan, but police said it was unclear if they were involved.
In October 2011, an Italian Catholic priest who had been helping tribal groups was shot dead as he was leaving his parish in Arakan.
In September, Oranza said police recovered and defused an improvised bomb planted near the school's flagpole.