Flights to Manchester Airport were halted for a short time after reports of a drone aircraft flying nearby with police called in to investigate.
A small number of flights have been diverted to other airports and other flights have been delayed after a potential drone sighting in airspace near the airport closed the airport for 20 minutes.
Greater Manchester Police's helicopter was called in to investigate the sighting. However, nothing was found.
"As the safety and security of all of our passengers is paramount, operations on Runway One were suspended for 20 minutes. Runway Two, which was unaffected, will remain open for an hour so normal traffic flows can resume," the airport said.
Manchester is the UK's third largest airport, with a record 22.32m passengers passing through the hub last year.
A "near miss" between a passenger plane and a drone occurred at London's Heathrow last year. The pilot of an A320 spotted the drone while flying at an altitude of 700ft and the two craft came within 20ft of each other.
The use of drones, or unmanned aircraft, is regulated by the UK's Civil Aviation Authority (CAA), and anyone flying the devices near congested areas must first apply for permission.