Copenhagen Airport was closed Monday night after drones were discovered nearby, an airport spokesperson told CNN.100 flights canceled.

Copenhagen Police said in a statement on X that “two to three large drones have been seen flying in the area,” and that it was unclear how long the disruption would last.

The airspace over the airport has been closed since 8:30 p.m. local time due to the “unidentified” drones, the airport spokesperson said. No flights have been allowed to take off or land.

The drones were still around the airport as of 11:17 p.m. local time, the airport said on X.

The airport will remain closed until 11 a.m. local time (5 a.m. ET), according to the US Federal Aviation Administration’s Notice to Airmen, or NOTAM system.

Departing flights from the Danish capital have been either canceled or delayed, the airport said.

Arriving flights have been redirected to other airports in Denmark, while some have been sent to Gothenburg and Malmö in Sweden, according to the airport.

This is a developing story and will be updated.