Parents of Muo Lisa and her male cousin were doing farm work when the two-year-olds came across unexploded ordinance

A grenade believed to be more than 25 years old killed two toddlers when it blew up near their homes in rural Cambodia, officials said.

The accident happened on Saturday in Siem Reap province’s Svay Leu district, where there had been heavy fighting in the 1980s and 90s between Cambodian government soldiers and rebel guerrillas from the communist Khmer Rouge. The group had been ousted from power in 1979.