Army Col. Alex Macario says Abu Sayyaf extremists most likely left the bomb, which was hidden in a biscuit can. It was found by troops Sunday in front of a school compound in Basilan’s Lamitan town.

Macario says the military has tightened security after a bomb destroyed a lodging house in the Christian town in predominantly Muslim Basilan late Saturday. No injuries were reported.

He says another bomb was found near a hotel in Basilan’s capital city of Isabela later.

Washington has blacklisted the Abu Sayyaf as a terrorist group.