Thick sheets of ice now cover a Chicago warehouse building, which burst into flames Tuesday night and reignited early Thursday.
Nearly 200 firefighters had to battle the five-alarm fire, the largest in seven years in the city, in single-digit temperatures with wind chills of more than 15 to 20 degrees below zero from Tuesday night into early Wednesday, which caused large amounts of water from the fire hoses to freeze across the building.
The fire rekindled early Thursday, which forced firefighters to pour more water on the already ice-covered building, according to the Chicago Sun-Times newspaper.
Deputy Fire Commissioner John McNicholas says, “when it gets encrusted in ice, we still have fire underneath that pile. As that fire starts to fester itself, eventually it gets more air and it starts to light up again.”
With eight inches of ice coating the outside of the building and the internal structure damaged by flames, officials say they are concerned the building could collapse under the weight of the ice.
"Things that normally work well in regular, normal, warmer temperatures, when you start to encase them in ice, you can have (problems)," said McNicholas.
The abandoned warehouse at the intersection of 37th and Ashland in Chicago's Bridgeport neighborhood used to be home to a furniture company, but it went out of business 10 years ago.
An arctic airmass, the coldest in nearly two years, settled over the region Saturday night, plunging temperatures well below freezing for daytime highs and nighttime lows.
The temperature on Tuesday fell to one below zero in the city. This was the first temperature below zero for Chicago since Feb. 10, 2011, when the temperature dipped to nine below zero.
Chicago temperatures are forecast to remain below freezing through the upcoming weekend before warmer weather pushes into the region early next week.
The cause of the fire remains under investigation.