This is the dramatic moment a toilet building collapsed as raging floods eroded its foundation.

Classes were being held at the Grace Jadeekho Church School when heavy rain triggered flash floods in the remote area in Tak province along the Thai-Myanmar border on September 28.

Dramatic footage shows the structure toppling into the muddy deluge surging from a channel during the storm. Teachers were heard screaming for pupils to stay away as the roaring torrent intensified.

Around 179 students and teachers had been evacuated during the chaos.

Locals said the area had been battered by downpours for days, sparking evacuations as floods submerged houses in the mountainous region.

Authorities later inspected the area and found the school's waterlogged bathroom toppled over after its base slipped into the currents. The school's kitchen and several classrooms and teaching equipment were also damaged.

Peter, 26, a teacher at the school for the underprivileged, said that on the day of the incident, staff had been monitoring for floods due to the heavy rain.

However, the water level had risen quickly, prompting teachers to evacuate the children to higher ground. There were no reports of injuries or casualties.

Thailand and neighbouring countries in Southeast Asia are in their annual monsoon rainy season which sees soaring temperatures followed by powerful rain storms in the afternoon leading to widespread flash floods.

Bangkok and large parts of the north and northeast of the country have been swamped with flash floods from tropical thunderstorms.