Colorado Springs firefighters battled a blaze in a vacant home on the 700 block of North Union Boulevard across the street from the Olympic Training Center for more than four hours Wednesday.

Smoke was visible coming from the structure shortly before 5 a.m. when a police officer reported the fire and the department's first alarm dispatched two engines, two fire trucks, the hazmat team and heavy rescue unit to the scene.

Access to Union Boulevard was blocked off from Dale to Willamette streets as fire crews and emergency responders swarmed the area, braving sub-zero temperatures and thick black smoke billowing from inside the house.

The fire was believed to have sparked in the basement and worked its way through the structure, keeping firefighters out for several hours and approaching the house from ladders, breaking windows to spray water inside, fire department spokeswoman Stacy Billapando said.

No one was inside the home when the blaze was reported but one firefighter suffered minor injuries, Billapando said.

"The fire damaged the inside of the building significantly and there was a possibility of a collapse on the south end of the structure, so firefighters have had to keep out for their own safety," Billapando said. "We believe the home was under construction or renovation."

Wednesday's brutally cold temperatures didn't help fire crews either, causing the water to freeze quickly and run off the structure, rather than dowse it. Firefighters expended all the water in their trucks and had to hook up hoses to the Olympic Training Center's water lines across the street.

"We had to use a lot of water and the run-off created a lot of ice, especially on the intersections of Union, so drivers should be very careful once the road reopens," Billapando said.