A small private plane crashed onto the roof of a suburban Chicago fitness center, officials with the Federal Aviation Administration said.
The Cessna 177 crashed just after noon Wednesday near Naperville, the agency said.
Two people were on board and their conditions were unavailable.
Aerial footage of the wreck showed that the Cessna hit a raised tower on the building's southwest corner, according to The Chicago Tribune.
A witness told The Chicago Tribune that police had blocked off the area and that he was able to see smoke spewing from the three-story building.
The Associated Press and NBCChicago.com also contributed to this report.