It was unclear what set off the explosion at the factory, Bogota mayor Carlos Galan said.

Emergency medical personnel and firefighters swarmed the scene, while images on social media showed a huge column of greyish smoke rising above the industrial town of Soacha late in the afternoon.

The powerful blast also blew out the windows of nearby homes.

“Health authorities report 33 people injured and one woman who unfortunately died,” Juan Sanchez Perico, mayor of the Soacha municipality, wrote on social media platform X.

He said earlier that the injured, including two in critical condition, were transferred to four different area hospitals.

According to local media reports, the explosion rocked the factory, known as Pyrotechnic Cowboy, just before 4.38pm.

The mayor said about 150 factory workers were evacuated from the premises after the explosion.

The structure, a large site built into the mountainside, was still burning yesterday evening, according to aerial images released by the Soacha mayor’s office.