Cambodian Mines Action Center expert found around 479 shells or 2.37ton in the bottom of the Tonle Sap lake on Monday.
This weapon has been found in wooden boat that sank in the civil war during 1970-1975, Heng Ratana, Secretary General of CMAC told Radio Voice of America.
Those shells are 105mm, 81mm,75mm, and 60mm artilleries shells.
The number of the weapon will me more tons because the searching operation still going on.
In the civil war there are around 5 to 6 millions UXO and mines are scattered through out the country in approximately 4,500km2.