A bus belched thick clouds of exhaust fumes on the road in Bangkok.

Footage shows the blue vehicle covering the area with white gas and obscuring visibility for other drivers and motorcycle riders in Thailand on December 27.

Onlooker Ekawin Chokprasoprauy said: 'The bus came from the Phaya Thai Line garage near the Ratchathewi District Office. It headed to the Victory Monument, and a lot of smoke was coming out.

'It continued to belch smoke for almost three minutes. It covered the entire place.'

Bangkok has become notorious for its chronic air pollution, which regularly exceeds the safe levels set by the World Health Organisation. This means the air quality is potentially deadly for sensitive groups, including children, the elderly, and people with respiratory problems.