THE Armed Forces of the Philippines (AFP) said Wednesday that there is a "big possibility" that terrorist bomb expert Basit Usman was behind the bombing in Cotabato City on Tuesday evening that injured four civilians.

The Army's 6th Infantry Division Public Information chief Dante Gania said the pieces of bomb recovered at the crime scene matches to the "bomb signature" of Usman.

A $1 million bounty is being offered for information leading to the arrest of Usman, who has alleged links with the Bangsamoro Islamic Freedom Fighters (BIFF).

Gania said they have received information that Usman is currently in the country to conduct bomb-making training to the BIFF members.

On the evening of August 20, a bomb planted in an wrangler-type jeep exploded causing injuries to three civilians and a soldier.

Gania said the hunt for Usman is ongoing. (Sunnex)