CHICAGO (CBS) — Police have found a University of Illinois student who disappeared after he checked in for a flight at O’Hare International Airport, but never boarded the plane.

Hye Min Choi, 19, has been reunited with his family. No additional details were released.

He was last seen on Saturday when he was scheduled to catch a flight to Greensboro, N.C.

The electrical engineering student, who also goes by the first name Joseph, had checked out of his dorm, took a bus to Chicago, and checked in his luggage on United Airlines flight 5892, but he never boarded the plane.

His mother was waiting for him in North Carolina and quickly realized he wasn’t on the flight.

Police said he did not re-book another flight with United.

Sources said Choi might have been upset over his final exams, but authorities would not confirm that.