MANILA — An ABS-CBN News source confirmed that the improvised explosive device detonated in Mindanao State University on December 3 was concealed in a black tote bag.

Authorities recovered the partially disintegrated black bag and several metal fragments from IED. The source said the bomb composed of a 60mm mortar round and RPG high-explosive anti-personnel MEUG.

The explosion left a crater on the gymnasium floor.

"Wala po silang nakita na any triggering device like battery operated or cellphone operated based doon sa mga nakumpleto nilang fragments at based sa reports sa atin kanina ito ay identifiable sa isang LTG operating in Mindanao which are 2 POIs are reportedly affiliated,” PNP acting spokesperson Police Colonel Jean Fajardo said in a press briefing in Camp Crame.

Fajardo added that based on the recovered fragments, the bomb is likely linked to a local terrorist group.

The bomb was placed in the middle of the gymnasium that left 4 people killed and 45 wounded.

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