An electrical fire occurred in the UW-Madison Engineering Research Building Thursday morning. No one was hurt; the costs of repairs are still being determined.

Although the actual cause is still under investigation, officials say the fire was due to an experiment in energy development entitled “Pegasus” in the basement.

After the first alarm was sounded, firefighters arrived to find thick, black smoke pouring from roof-area vents. A second alarm was initiated because of possible life-safety concern.

The basement fire was quickly knocked down, but the smoke vented to the top floors and roof area. To ventilate the smoke out of the building, the crews shut the stairwell doors to the west end and opened the east-end stairwell doors. Starting with the first floor and working their way up to the 14th floor, crews pushed the smoke out with positive-pressure fans.

Connie Brockman, assistant dean of the College of Engineering, said she was not concerned about the fire.

“I’m sure everything is just fine,” Brockman said.

Brockman was unable to give an estimate of the costs of the fire, but said she did not believe there to be structural damage. Firefighters said there was fire, heat and water damage to the basement of the building.