CHICAGO (CBS) — The recent arctic blast has made the already demanding job of fighting fires even more dangerous, and the last few days have been especially bad, as temperatures lingered in the single digits from Monday night until Thursday morning.

An inferno greeted firefighters at a house near Mason and Madison late Wednesday night. The blaze was so intense, firefighters could only attack it from outside. Even that proved to be life-threatening when a transformer blew, causing a live wire to fall in front of the house.

The wire continually arced, trapping several firefighters in the front yard. That forced rapid intervention team members to bring in a saw to cut through the fence and rescue their colleagues.

Two firefighters were checked out at the scene, but were expected to be okay, despite being trapped next to a house fully engulfed in flames.

Before dawn Thursday, a building at 119th and Peoria caught fire. Numerous firefighters found their gear glazed in a thin coating of ice as they worked in temperatures near zero.

A warming bus was brought in to guard against frostbite.

A massive tow truck also was called in, after one of the hook and ladder trucks got stuck in the ice when the water used to douse the fire froze before it could drain from the side yard of the building.

According to the American Red Cross, there were at least nine fires in the Chicago area on Wednesday, when temperatures were in the single digits all day. At least 25 adults and 15 children were forced out of their homes.