A potato farmer who unearthed old bullets as he ploughed his field on Friday in Oddar Meanchey province discovered more than 500 pieces of unexploded ordnance, anti-mine officials said yesterday.

Farmer Hun Kren, 29, alerted authorities to the discovery in Banteay Ampil district, where Cambodian Mine Action Centre personnel found a hole containing a total of 501 mines, grenades, rockets and bullets.

Officials concluded that the ordnance was left over from Khmer Rouge fighting in the 1980s or ’90s.

“In the mine fields, you don’t normally find numbers like that, but this was one cache found in a hole. This was a storage for people trying to hide the mines to be used later,” said CMAC director general Heng Ratana.

CMAC destroys some 150,000 pieces of UXO every year, Ratana added.

According to research by the Cambodian Mine Victim Information System, Oddar Meanchey remains a high-risk province for land mines and explosives and has the second-highest mine casualty rate nationally.

Within the first six months of 2013, 15 mine casualties occ­urred in the province.

“We have destroyed … around 200 [mines] every month since 2005,” said CMAC officer Thuch Chantola of Banteay Ampil district.