Soldiers and ordinary citizens in the Lao capital Vientiane on Thursday raced to build up barriers along the Mekong river as water levels rose past the flood danger level, authorities said.
"The water is still rising… we're working on building higher levees," foreign ministry spokesman Yong Chanthalangsy told AFP by telephone.
So far, the barriers seemed to be holding, with only a few sections of the capital under a few inches of water, he said, even though the Mekong is at its highest level since 1966, when floods ravaged the impoverished country.
Large swathes of Laos have been inundated by flood waters for the past month, the spokesman said, including Luang Prabang province — home to the ancient royal capital of the same name that is a UNESCO World Heritage site.
The situation deteriorated last weekend when powerful tropical storm Kammuri swept through the country.
So far, the floods have killed four people and tens of thousands of hectares of rice fields have been destroyed, officials said.