Hun Sen is a wily survivor of Cambodian politics and the wider tumult across Southeast Asia over the last half-a-century. Born to rice farmers in a province heavily bombed during the secret U.S. war in Cambodia and Laos, he became a soldier for the Khmer Rouge, whose murderous regime from 1975 to 1979 killed about a quarter of the population.

Casualties include an 8-year-old Thai boy and multiple Cambodian civilians. Thousands of displaced families are sheltering with monks, NGOs and volunteers as schools and markets close across the border region.