"At 08:45 a drone was spotted in the vicinity of Francisco Sa Carneiro Airport", said an official source from the company that manages national airports.
The same source said that "air traffic control kept the landings on hold for a few minutes, and there was a divergence to Lisbon, from a flight from Lyon", in France.
According to the airport's website, the flight in question, from Easyjet Europe, ended up arriving in Porto at 11:09 am, more than two hours later than expected, after the detour to Lisbon.
ANA states that even with this morning's incident, there was "no other impact on the operation", which "is running normally".
The regulation of the National Civil Aviation Authority (ANAC) prohibits the flight of drones (unmanned aerial vehicle) at more than 120 meters in height and in the approach and take-off areas of airports.