A concrete block plunged onto a busy road when a crane hoist snapped during a botched building demotion.

The huge slab was being carried by the machine when it fell and tore through scaffolding around the building in Bangkok, Thailand, on December 14.

Footage shows the block dragging the cable from the crane down with it, peeling off debris and crashing into traffic on the road below.

The electrical wires that were hit exploded and rained sparks below before another explosion happened. It damaged three pickup trucks parked beside the pavement below.

Officials said that nobody was injured in the accident at the Sri Fueang Fung Building in the capital.

Police chief Thanasak Phanchoti, from the Thung Maha Mek district station, said: 'The accident damaged a worker's truck and two other cars on the other side of the road.

'There were also power lines that were dragged, but no one was injured or killed.'

The officer added that the demolition project company immediately removed the concrete block and debris.

Authorities are now investigating the cause, whether it was equipment or human failure. They said the contractor would be fined for the blunder.