They will inspect it, including checking for fingerprints, to determine whether it was used in a previous attack in the restive deep South.

Forensic police will also determined if it was one of the guns stolen from the 4th Engineering Battalion at the Narathiwat Rajanakarin Camp in January 4, 2004, or from the Phra Ong Dam military base in Rangae district on January 21, 2011.

The M16 was found at about 9.30am on Monday after a local resident tipped off authorities about a man hiding a gun to the wooded area at Ban Bakong Moo 6 in tambon Rusoh.

Officers believe that the rifle was hidden there to be later retrieved for use in an attack in Rusoh.