Of those injured, two were listed in critical condition, three had suffered serious injuries and one suffered minor injuries and was later discharged from a hospital, Evans said.
Video shows that downed crane ripped a large hole in the side of the building. It also damaged an adjacent parking garage and some of the vehicles in it.
The crane fell after the National Weather Service issued a severe thunderstorm watch for the greater Dallas/Fort Worth area, warning of heavy rain, damaging gusts and large hail.
The agency also issued a flood advisory for parts of the region.
The weather service says winds could exceed 112 km/h. At Dallas Love Field airport, WFAA-TV reports gusts damaged a hangar door and part of the roof at a Southwest Airlines maintenance facility.
- AP