Thousands of sandbags were used to secure a giant sinkhole on a collapsed road in Bangkok.

Authorities dumped some 50,000 sandbag sacks into the abyss to protect nearby buildings from collapsing on Wednesday evening.

Footage shows heavy equipment lowering the material into the chasm near a hospital and a police station.

Bangkok governor Chadchart Sittipunt said the measure was carried out to keep more soil and water from flowing into a cracked section of the underground tunnel.

He added that concrete will be poured into the sandbag reinforcements to increase stability and stop soil subsidence as ground movement was still being detected.

Officials said the nearby Vajira Hospital was relatively secure because of its underground concrete walls. However, a new five-storey police station in the area was in danger of collapsing after its foundation was eroded.

The road collapsed on Wednesday morning due to the botched construction of an underground train line that caused a burst water pipe. The earth then gave way - sucking in several vehicles and power lines that exploded in a flash of sparks.

Miraculously, nobody is believed to have been injured. However, officials said 'two or three' police vehicles had been lost in the sinkhole.

Bangkok Governor Chadchart Sittipunt arrived at the scene at 8 am to assess the situation. He said recent construction from an underground train for the city's MRT purple line may have contributed to the collapse.

He said: 'Once the road was damaged, debris from the surface poured into the underground construction void, causing the area nearby to fall inside.

'A water pipe was damaged, causing a leak, which contributed to the issue. Nobody was injured, but damage to nearby buildings, including a new police station, is being assessed.'

Prime Minister of Thailand and cannabis campaigner Anutin Charnvirakul later arrived.

Police Lieutenant General Sayam Boonsom, commissioner of the Metropolitan Police Bureau, said the area was undergoing roadworks at the time of the collapse.

Officers said a damaged water pipe could have further caused the earth to weaken.

The police chief said: 'A preliminary assessment has found that construction activity may have caused the ground to sink and form a cavity underneath. The ground continued to subside.

'The area is being secured and investigations are ongoing into the cause, with several organisations working to assess the damage and the structural safety of the road.'