Stock of empty and live ammunition was discovered in a well in Nawaththegama-Thammenawatiya area.
An RPG bullet and 9960 empty bullet casings for T56 assault rifles were recovered at the location by the police.
It was diffused by the Officers of the Puttalam Special Task Force.
It is suspected that someone who collects old iron may have brought these ammunition.
Nawagattegama police are conducting further investigations.