The Philippine military has placed the country's troubled south under "extreme alert" after a string of deadly bombings.
Military chief General Hermogenes Esperon said Thursday, government troops and police have intensified security patrols because of the possibility of more terrorist attacks.
He noted specific concerns about operations by the local militant group Abu Sayyaf and Jemaah Islamiyah, a Southeast Asian terrorist network linked to al-Qaida.
Three bombs ripped through the southern island of Mindanao Tuesday and Wednesday, killing at least six people and wounding 29.
Philippine forces have been fighting Abu Sayyaf on the southern island of Jolo.
The militants are believed to be aiding Dulmatin and Umar Patek, two key members of Jemaah Islamiyah wanted in connection with the 2002 bombings in Bali, Indonesia.