Locals in the northern province of Thai Nguyen said that several utility poles in their neighborhood suddenly caught fire on Monday afternoon.
Witnesses said the incident occurred around 3 p.m. on Monday. They first heard loud explosions and saw some sparks from a few poles.
The flames then spread along the overhead power lines to even more poles.
Firefighters were mobilized to the scene soon later. It took them 35 minutes to completely stop the fire.
In a picture captured by a local, black smoke can be seen rising from two of the burning poles.
Locals did not suspect anything unusual before the fire and believed that the cause could have been the intense summer heat.
“We were so scared that we all fled away right after seeing the fire,” said Nguyen Van Minh, a local.
Investigators are looking into the case.