DENVER -- Crews were cleaning up after an electrical fire in the 42-story Brooks Tower on the corner of 15th and Curtis streets at daybreak Friday.

It started in an electrical box on the ninth floor around 3:30 a.m. and caused smoke and fire damage on the next three foors.

More than 75 residents between the eighth and 12th floors were evacuated and many will likely be displaced for several days, officials said.

Two were transported to the hospital for smoke inhalation.

The exact cause of the fire is under investigation.