The Armed Forces of the Philippines (AFP) have been put on red alert following an explosion at a public market in the southern Philippines, the military said Monday.

"Red alert is declared to all AFP units nationwide effective 9:00 p.m. Sunday," said AFP spokesman Lt. Colonel Buenaventura Pascual.

On Sunday afternoon, a bomb exploded at a public market in General Santos City of South Cotabato province, leaving at least 15 dead and 67 injured.

Immediately after the attack, AFP's Southern Command has ordered intensified security in vital installations in the city.

Task Force GenSan, a military and police joint group, has started investigating the incident.

"As of this time, Task Force GenSan has no suspects yet and no motives established yet. No group has accepted responsibility on the bombing," Pascual said.

Police said that they have received reports of threats by the rebel group of the Moro Islamic Liberation Front (MILF), which allegedly is linked to the southeastern terrorist network, Jemaah Islamiyah (JI).

However, the local government of General Santos believed that the incident was caused by feuding merchants.

Last April, a major bomb attack in the city killed 15 and injured dozens when an improvised explosive device ripped through a crowded shopping mall, which was blamed on Abu Sayyaf rebels.

Source: Xinhua