An engine shut down on a United Airlines jetliner Sunday, forcing it to make an emergency landing in western Colorado with 125 passengers and crew on board.

The Boeing 757 was flying from Denver to Los Angeles when one of its two engines shut down, and the flight was diverted to Grand Junction Regional Airport, typically a landing spot for smaller aircraft.

Passenger Jim Schreckengast said ground crews at first had trouble finding stairs high enough to reach the door of the 757.

The plane landed safely at about 11:44 a.m., Federal Aviation Administration spokesman Ian Gregor said. No injuries were reported.

United spokesman Charlie Hobart said he didn't know the nature of the problem, or whether the crew shut down the engine or it stopped on its own.

Amy Jordan, deputy director at Grand Junction airport, told the Denver Post (http://bit.ly/vMydB0) that "the engine had problems shortly after takeoff."

Schreckengast, of Fort Collins, Colo., told The Associated Press that the pilot announced over the public address speakers that the engine had lost oil volume.

Schreckengast said passengers remained calm and no one appeared to be afraid.

"There was some applause when we landed," he said. "I think the crew handled it very well."

Hobart said United was sending another plane from Denver to pick up the passengers in Grand Junction and take them on to Los Angeles.