ZAMBOANGA CITY (4th UPDATE)—Eight people were killed, including 3 soldiers and 2 suspected bombers, in twin explosions near a military camp in Barangay Kajatian, Indanan town, Sulu on Friday afternoon.

Three civilians were also killed, while 12 others were wounded, according to Major Gen. Cirilito Sobejana, commander of Western Mindanao Command.

Sobejana said 3 suspicious persons were flagged down at a security checkpoint. However, only one of them was seen by the soldiers carrying a suspected improvised explosive device placed inside a bag.

The person was then escorted to the guard house of the military camp, but as soldiers were about to again inspect the bag, the bomb went off.

After the first bomb exploded, one of the suspect's companions suddenly ran toward the military camp, and a few seconds later the bag that he was carrying also exploded.

Sobejana said the military is still checking if the bombs were remotely triggered.

"This attack is meant to disrupt the intensified security operations and our operational tempo following series of recent operational gains in the area," said Lt. Col. Demy Zagala, spokesperson of the Philippine Army.

Military officials said the Abu Sayyaf group, an Islamic State-linked terrorist organization, could be behind the midday blast.

"We're not discounting the possibility that it's the handiwork of Abu Sayyaf Group," regional military spokesman Major Arvin Arcinas told reporters after the attack on the special counter-terrorism unit's temporary headquarters.

The victims were rushed to a military hospital in the province.

Metro Manila police have been raised on full alert after the explosions. National Capital Region police chief Major Gen. Guillermo Eleazar said the alert was raised as a "proactive means" in response to the Sulu blasts.

—With reports from RJ Rosalado, ABS-CBN News and Agence France-Presse