The fire started at the Brandywine Building on the 1000 block of West Street in Wilmington around 6:15 a.m. Friday.
Emergency officials tell Action News that the fire, which started in an elevator, sent smoke throughout the upper floors of the high rise. The Brandywine Building houses offices and condominiums.
The fire was confined to the inside of the elevator car. The car was heavily damaged by fire.
No injuries were reported from the fire or the evacuations.
The Wilmington Fire Marshal's Office responded to investigate and has determined the cause to be electrical.