This is the shocking moment an electric transformer exploded into a giant fireball at a road intersection in Thailand.

CCTV footage shows the device erupting in a huge blast next in a busy area of Kalasin province on August 31 morning, emitting a mushroom cloud of smoke as fire engulfed the power lines.

The local fire department arrived 15 minutes later and brought the blaze under control.

Onlooker Sawad, 54, who owns a tailor shop near the intersection, said firefighters took about 30 minutes to extinguish the flames, adding it was not the first time the transformer had exploded.

He said: 'The transformer had exploded four times before, but today is by far the worst. It was really loud. Luckily, nobody was near when it happened.'

The Kuchinarai District Provincial Electricity Authority said it is probing the cause of the incident, which is believed to have sprung from a transformer malfunction.

A spokesman for the office said: 'We would like to confirm that the transformer's maintenance is not neglected in any way. What happened was an accident.

‘Currently, the Kuchinarai Provincial Electricity Authority has coordinated with the relevant officials to inspect and complete the replacement of the new transformer.'

Kuchinarai District Sheriff Weeradon Siri added: ‘I have been informed about the incident. Nobody has been injured and there were also no reports of damage to nearby residences.

‘However, I have instructed relevant departments to regularly inspect the electrical transformers at different points to prevent such incidents from happening again.'