An airport employee sustained critical injuries when a passenger aircraft collided with a tug at one of the nation’s busiest airports, as reported by Chicago Police.

According to the FAA’s website, “Air Wisconsin Flight 6181 struck the tug while preparing to dock at Chicago O’Hare International Airport around 7:35 p.m. local time on Saturday, Feb. 1.” The aircraft involved was identified as a Bombardier CRJ-200, which was operated on behalf of American Airlines by American Eagle.

Chicago Police indicated that the plane’s wing made contact with the tug as it was crossing a taxiway.

“The tug overturned, trapping the driver beneath it,” stated the Chicago Police in a message to YSL News. “The individual driving the tug, a 64-year-old man, was taken to Lutheran General Hospital in critical condition but has since been stabilized. He suffered injuries to his head and lower body.”

Both the driver and the tug were employed by United Airlines. “We are making sure he gets all the necessary support and care,” United commented in a statement.

American Airlines reported that no passengers on the plane were injured; they disembarked safely and were escorted to the terminal. The Chicago Department of Aviation noted that this incident did not significantly disrupt operations at O’Hare. American emphasized that the accident occurred on an active runway after the flight arrived safely from Kalamazoo/Battle Creek International Airport in Michigan.

“Ensuring the safety of our customers and team members is our foremost priority, and we are currently investigating this incident,” American further stated.

Both the Chicago Police and the FAA are conducting inquiries into the event.

(This story has been updated with additional information.)