Munich airport has been closed after drone alarms, German Bild reports.

The first alarm came at 9:30 p.m. on Thursday evening and an hour later the observations were confirmed by police on site, according to the newspaper. 

Both runways were closed, affecting over 30 flights and 3,000 passengers.

A search operation was launched, including with the help of a police helicopter, but neither the drone nor the perpetrators have been located.

The airport is normally closed from midnight to 5 a.m. It is unclear whether Friday's air traffic will be affected.

Source: Aftonbladet.se