GREECE’S transport minister said today that a major radio communications failure that shut the country’s airspace a day earlier is unlikely to have been a cyberattack, though the cause remains under investigation.

Flights across Greece were grounded, diverted or delayed for several hours on Sunday after noise was reported on multiple air traffic communication channels.

“It does not appear to be a cyberattack,” Transport and Infrastructure Minister Christos Dimas told public broadcaster ERT.

He described the disruption as “a very serious incident” but stressed that passenger safety was never at risk.

The Greek Civil Aviation Authority said noise across all channels, including backup systems, triggered the shutdown, which lasted several hours before operations were gradually restored.

Incoming flights were diverted to several countries in the region, creating a large backlog and leaving thousands of passengers stranded.

The Air Traffic Controllers’ Association said that the outage underscored its calls to modernise and replace outdated equipment.

A judicial inquiry and an internal investigation were launched Monday into the cause of the outage.