Vernon fire: Visuals capture heavy smoke filling the sky, flames engulf commercial building | Watch

Firefighters are battling a second-alarm fire at a commercial building in Vernon, later upgraded to three alarms.

The fire is at the Alcon Transport Company, a trucking business in the 4600 block of Hampton Street.

Thick smoke and large flames engulfed the building, destroying at least one warehouse and damaging a nearby building.

The cause of the fire is unknown, and no injuries have been reported as of Thursday afternoon.

Nearby train tracks were shut down, and crews remain on site checking for hotspots.