IMPERIAL, Pa. (AP) — A United Airlines maintenance team is trying to determine what caused a report of smoke aboard a flight from Newark, New Jersey, to Pittsburgh.

Pittsburgh International Airport spokeswoman JoAnn Jenny says the United Express flight landed safely just before 10 p.m. Monday, but passengers had to get off the plane on the runway as a precaution.

The flight crew reported smoke to the Pittsburgh control tower about a half hour before the flight landed. Emergency crews found no fire on the plane and couldn’t find the source of the smoke.

United spokeswoman Mary Ryan says the smoke appeared to be coming from the plane’s cargo area. Maintenance crews were inspecting the plane on Tuesday.

The Q400 aircraft was carrying 59 passengers and four crew.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.