Pro-Islamic State (ISIS) militants stormed a school in the southern Philippines early on Wednesday (local time) and are holding several students hostage, police said, according to Reuters.
The incident took place on the same island where fighting between government troops and Islamists has entered its fifth week.
So far there have been no reports of any fatalities or injuries.
A police report said about 300 armed men, among them members of the Bangsamoro Islamic Freedom Fighters (BIFF), stormed a school in Pigcawayan town in North Cotabato province on Mindanao island and were holding some students captive.
Members of the BIFF were engaged in a gunbattle with the military, Chief Inspector Realan Mamon, the police chief at Pigcawayan, said in a radio interview, according to Reuters.
"We can confirm that they occupied a school and there were civilians trapped. We are in the process of determining how many were trapped and their identities," Mamon said.
Pigcawayan is located 190 kilometers (120 miles) south of Marawi City, where BIFF militants, along with fighters from other groups allied to ISIS, have been holed up and fighting the Philippines military since May 23.