Volta Redonda, Brazil – A towering mushroom-shaped cloud of reddish-brown smoke rose over one of Brazil’s largest steelworks on Wednesday afternoon, October 28, after an explosion startled residents across the city of Volta Redonda.

Footage shared on X by journalist Ruan Campos shows the dark column of smoke billowing high into the grey sky above trees and buildings, as cars drive along a city street in the foreground. “The huge impact of the explosion made doors and windows shake,” Campos wrote, adding that residents in different neighbourhoods said they felt it.

The steelmaker CSN said the blast happened at about 1:30 p.m. at its Presidente Vargas plant, while molten pig iron was being unloaded from a rail tanker car into a slag pit. Contact between the very hot material and excess moisture in the ground caused a violent reaction, releasing heat and smoke that could be seen inside and around the plant, the company said.

Firefighters said the plant’s own fire brigade put out small initial fires, and that a sweep of the site found no victims and no flames. Police are investigating, and the state environment agency said CSN could be fined for air pollution.

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