A fire that ignited Saturday in Pueblo’s midtown area has been mostly extinguished, fire officials said.

The Pueblo Fire Department used heavy machinery to break up the burning pile of railroad ties, separating burnt material from unburnt material, said Tim Trujillo, the department’s public information officer.

The fire will continue to smolder through the night, Trujillo said. The railroad will monitor it overnight, and the Fire Department will return in the morning to mop things up.

The fire was first shared via videos clips on social media about 12:40 p.m. Saturday. The clips showed a thick column of black smoke with large, visible flames.

One video appeared to show a Fire Department vehicle on scene dousing the fire with water.

It’s unknown what sparked the fire. Once the blaze is out, fire officials will conduct an investigation and share further updates, Trujillo said.

The Fire Department advised residents with respiratory issues or those downwind of the fire to take the necessary precautions to avoid inhaling the smoke.