ARLINGTON, Va. (AP) Several tons of freshly poured concrete collapsed from the roof of a high-rise construction site on Friday, injuring 16 workers on the floor below, some seriously, authorities said.
The concrete collapsed from the roof of the 300-foot tall skyscraper onto the 24th floor because it was apparently too heavy for the scaffolding holding it up, said Capt. Tom Polera, a spokesman for the Arlington County Fire Department.
Sixteen workers and one firefighter were injured, authorities said. Fire officials initially reported three people in critical condition; a check of local hospitals turned up only one.
About 200 workers were in the building when the roof caved, dropping a 25-by-25-foot section of fresh concrete and debris onto the workers, Polera said. Two people became stuck in a heavy mud that slowly started hardening, authorities said.
``I heard the noise, a big boom like an explosion, and I heard people yelling,'' Yancy Figueroa, who was working in another building at the construction site, told The Associated Press. ``There was concrete everywhere, between the beams. There was lots of stuff on top of people.''
Alexandria firefighter John Vollmer, whose unit assisted Arlington emergency personnel at the scene, said the falling concrete would have been ``like a freight train coming through.''
``Concrete is about 7,000 pounds per cubic yard, and the whole floor fell. You're talking a lot of weight,'' he said.
Vollmer said one worker was trapped in the concrete from the waist down, conscious and breathing. Rescuers used air bags and a construction crane that was at the site to lift the steel and concrete off the man so rescuers could slide him out, Vollmer said.
The man was hospitalized in critical condition.
Clark Construction, the contractor, had planned to hold a ``topping-off party'' Friday to celebrate completing the pouring of concrete, said Brian Abt, a company official. Arlington County building inspector Mike Lewis said he was not aware of any unusual problems in any of the company's projects in the county.
Virginia occupational safety officials and Arlington County Police were investigating the accident. An initial review showed no major safety violations at the work site, said Jennifer Wester of the state Department of Labor and Industry.