Friday, February 15, Dubai International Airport had to stop flights for a short period of time, between 10:13 a.m. to 10:45 a.m., “due to suspected drone activity,” according to the Associated Press (AP).

Being one the busiest international airports in the world, closures like this can be costly. In 2016, the airport closed a total of three times from nearby drones, which AP says “cost millions of dollars.”

As Dubai suffered last week, Dublin becomes this week’s target. Flights at Ireland’s Dublin Airport were suspended for 30 minutes Thrusday, February 21, after a pilot confirmed a drone sighting over the airfield. According to AP, normal flight operations resumed after the 30-minute window. However, during the suspension, three incoming flights were redirected to other airports, and delays were felt throughout the entire day.

Dubai and Dublin are the latest in the string of airports budding heads with drone activity. London’s Gatwick airport comes to mind, shutting down for three days during the Christmas travel rush, which delayed more than 100,000 people, AP reports.

In response, the U.K. recently extended the 0.6 mi (1 km) no-fly zone for drones to 3.1 mi (5 km), which will come into effect March 13.

The drone airport saga even hit closer to home, disrupting Newark Liberty International Airport in New Jersey last month, which grounded all departing and incoming flights. The drone came within 30 ft of an aircraft.