A video uploaded to a social media website showed aerial footage of flooded fields in Attapeu province in Laos on Wednesday after a dam collapsed and sent a deluge of water across a swathe of villages.
Rescue teams from China and Thailand headed on Wednesday into a remote part of landlocked Laos, where flooded fields have stranded more than 3,000 people.
A United Nations report on the disaster put the death toll at five, with 34 missing, 1,494 evacuated and 11,777 people in 357 villages affected. It said 20 houses were destroyed and more than 223 houses and 14 bridges damaged by the flooding.
However, a government official said hundreds were reported missing after at least seven villages were submerged in the southernmost part of the country.