Laos construction workers scramble as dam overflows upstream

Troubling video filmed in Laos has shown construction workers fleeing for their lives after a dam overflowed upstream.

The video uploaded to YouTube this week shows the panic at a construction site as a mass of brown water and trees overwhelm the banks of the Nam Ao River last Monday.

A tractor is left unattended and begins rolling backwards on its own accord as a man in a ute tries to get around it.

Eventually the whole site is flooding, swamping cars and construction machinery.

But the president of Bothong Inter Group, the hydropower company building the dam, said they were not responsible for the flood.

It was heavy rain from upstream that caused the nearly finished dam to overflow, the Vientiane Times reported.

The flooding damaged crops and vehicles in downstream villages, but no casualties were reported.

The hydroelectric dam was scheduled to start generating power later this month.