An electrical issue in the air traffic control tower Monday afternoon caused smoke to come out from behind the equipment but fire crews were not able to determine the cause of the smoke.

A call to the emergency dispatch just before 2 p.m. reported smoke in the tower, and the Aspen Fire Department responded with three trucks and about 15 firefighters. No flames were reported.

Neither the tower nor the terminal at Sardy Field had to be evacuated, and there were no reports of injuries.

“The controllers noticed some smoke coming out of their consoles, so they called the Fire Department, which is always a good thing to do,” airport director John Kinney said Monday afternoon. “They came out and checked it out and gave it the all clear.”

Aspen Fire Chief Rick Balentine said they could not find the cause of the smoke but everything was back to normal after about 45 minutes from when the call came in.

“It was coming behind from one of the panels. When I got there you could still smell the electrical smell, but the smoke had dissipated,” Balentine said. “After investigating we couldn’t find cause, but told the controllers if it happens again to call 911.”

There was a United flight coming from and then flying back to Denver that was delayed, but Kinney said it was not because of the report of smoke. He was told it was a crew staffing issue.

Other agencies, including the Pitkin County Sheriff’s Department, were on scene. In all, Balentine estimated there were about 25 officials who responded. The scene was cleared just after 2:30 p.m.