Planes diverted, flights delayed after air traffic control tower evacuated at Sky Harbor Airport

PHOENIX (KSAZ) - Phoenix fire says an air handler issue caused a fire alarm to go off in the control tower at Phoenix Sky Harbor International Airport Sunday morning, causing multiple flights to be diverted and delayed.

The air traffic control tower was evacuated as a precaution after an alarm activated. Because of this, 40 inbound aircraft were diverted to nearby airports, including Mesa Gateway and Tucson.

Tower employees are now returning.

The issue has been turned over to maintenance crews at Phoenix Sky Harbor.