CHBAR MON, CAMBODIA -- A funeral was held Sunday for 20 soldiers who died at an army base in southwestern Cambodia in a huge explosion of stored munitions that also wounded several others and damaged nearby houses.

There has been no public explanation of what caused the Saturday afternoon blast at the base in Kompong Speu province, though there were no suggestions it was triggered deliberately.

Defense Minister Tea Seiha, representing Prime Minister Hun Manet, presided over the Buddhist funeral ceremony, which was attended by relatives of the victims and fellow soldiers. Cambodian flags covered the wooden coffins.

A villager living nearby told The Associated Press on Sunday that he trembled after hearing the blast because he had never before experienced such a loud explosion.

“When the explosion happened, I was fixing my house with some construction workers,” said Chim Sothea. “Suddenly there was a loud explosion, causing my house to shake and breaking tiles on my roof. They fell down but luckily they didn’t fall inside the house.”

Images showed several badly damaged buildings on the base, at least one with its roof blown off, and soldiers receiving treatment in a hospital. Other photos showed nearby houses with holes in their roofs.

Four buildings on the base — three for storage and one work facility — were destroyed and several military vehicles damaged, Col. Youeng Sokhon, an army officer at the site, said in a report to army chief Gen. Mao Sophan.

Another villager, who asked to be named only as Sophal, said the military closed the road to the base and “villagers were in a panic, seeking a safe place.” He moved his family to his parent’s home, farther away from the base. When he returned to his own house hours later, he found it undamaged but other villagers’ houses had broken windows, doors and roofs, he said.

Cambodia, like many countries in the region, has been suffering from an extended heat wave, and the province where the blast took place registered a high of 39 C (102 F) on Saturday. While high temperatures normally can’t detonate ammunition, they can degrade the stability of explosives over a period of time, with the risk that a single small explosion can set off a fire and a chain reaction.

In March 2005, a nighttime blast at an arms depot in the northwestern provincial town of Battambang triggered an hourslong spray of shells and bullets, killing at least six people and causing panic.

A 2014 report by the Swiss-based group Small Arms Survey highlighted the dangers of poorly stored or mishandled munitions, calling it a “global problem.” It noted that from 1979 through 2013 there were more than 500 incidents involving unplanned explosions at munitions sites.