East Midlands Airport had to close its runway and divert a number of flights after drones were spotted nearby.
Eight services were diverted to different airports on Friday evening after drones were spotted around a mile away near Donington Park in Leicestershire, where Download Festival is taking place this weekend.
The airport was forced to close the runway for 30 minutes, which caused the disruption.
In a joint statement, Download, Leicestershire Police and East Midlands Airport said: "Recent reports of drone sightings near Donington Park have resulted in some operational disruption at East Midlands airport in recent days.
"This has affected both the night-cargo operation and passenger have been diverted to other airports.
"The safe operation of the EMA aerodrome and the safety of the public at the event are our top priority.
"Together, Leicestershire Police, Download festival organisers and the airport continue to work closely to monitor the situation.
"As a result, both the festival organisers and the police have enhanced the number of patrols on site and the surrounding areas."
Flying drones near airports is a criminal offence under the Civil Aviation Act 1982.
Over the Christmas period in 2018, alleged drone sightings around Gatwick airport resulted in its closure for more than a day, which disrupted more than 1,000 flights.
A police investigation was launched, costing the taxpayer hundreds of thousands of pounds, but no one has yet been brought to justice.