Update:

A construction worker was in critical condition Monday afternoon after a floor collapsed at the Thompson Block construction site.

A full floor fell on top of the worker at the historic building in Ypsilanti's Depot Town.

The worker, who was unconscious, was taken to St. Joseph Mercy Hospital, according to Ypsilanti Fire Department Capt. Dan Cain. The worker's name and age were not available.

The historic building, 400 N. River, is currently under construction after a 2009 fire gutted the building. Construction began Dec. 23. The development plans call for first-floor retail space and lofts above.

On Monday morning, building owner Stewart Beal tweeted that the first floor of the building was being demolished today.

Demolition of 1st floor 5-11-15 — Stewart Beal (@stewartbeal) May 11, 2015

Cain said crews arrived on scene in two minutes after getting the call at 11:45 a.m. It took roughly 22 minutes to stabilize the structure and get the injured worker out.



A combination of area first responders along with the Washtenaw Technical Rescue Team were all on the scene.

Getting the injured worker out wasn't so simple.

"If you move the wrong piece of lumber at the wrong time you're going to make the problem worse," said Cain. "It's not just a matter of grabbing stuff and throwing it off."

Cain estimated that the emergency crews wouldn't be the scene for that much longer. The crews needed to fully secure the building before letting investigators in.

The cause of the collapse is under investigation.