Firefighters are still on the scene of a warehouse fire in the Bridgeport neighborhood.
The fire is mostly out, but crews are searching for hot spots.
At its peak, 170 firefighters were needed to get the flames under control.
The fire broke out in a vacant building in the 3700 block of South Ashland, just after 9 p.m. Tuesday.
It was called in by a fire department chief who was driving by.
The cold weather made it difficult on crews, who had to deal with frozen hydrants and ice from their hoses.
One firefighter suffered a back injury, but no one else was hurt.
The cause of the fire is under investigation.