Major European airports including Brussels, Berlin and London's Heathrow were Saturday hit by a cyberattack on check-in systems that caused cancellations and long delays for thousands of passengers. 

Dublin and Cork airports in Ireland were also affected, Dublin airport said on X, adding that it was experiencing "minor impacts" from "a Europe-wide software issue".

According to aviation watchdog Eurocontrol, the airports were "reporting disruptions in IT systems related to passenger handling."

At least 10 flights were cancelled out of Brussels Airport and another 17 delayed by over an hour after the system was hit by a "cyberattack" late Friday, the airport said.

"We have become aware of a cyber-related disruption to our MUSE software in select airports," airport service provider Collins Aerospace told AFP.

"The impact is limited to electronic customer check-in and baggage drop," added Collins Aerospace, which says it has a presence in 170 airports globally.

Brussels airport said the attack was still having a "large impact" on flight schedules on Saturday.

"In terms of information, it's really not good at all, people are waiting, people don't know," Nancy Steiner, 53, told AFP while surveying the long queues of passengers at Brussels airport.

Airlines had been asked to cancel half their flights to and from Brussels between 0400 GMT on Saturday and 0200 GMT on Monday because of the attack, Eurocontrol said.

AFPTV reporters filmed large queues at Brussels as passengers anxiously monitored announcement boards showing many flight delays.

London's Heathrow Airport -- the busiest in Europe -- said its check-in and boarding systems, also provided by Collins Aerospace, were hit by a "technical issue" that "may cause delays for departing passengers".

'Queues not moving'

"They didn't tell us anything. It's always crowded here, but today is like extra," said a 41-year-old architect waiting in Heathrow, who gave her first name as Rowan.

"If the system is down they should delay the flight. That's what I'm hoping," she added, waiting in the packed check-in area at Heathrow's Terminal 4 for a Saudia Airlines flight to Jeddah.

Another woman waiting for an Air Algerie flight to Algeria said she had been queueing for more than an hour to check in.

"They said they're doing everything manually. That's all they've told us," said the 30-year-old, asking not to give her name.

Pranit Nevrekar, 32, dropping his parents off for the Jeddah flight, said: "We've been told there's a disruption across Europe. So the check in system isn't working, they're doing everything manually."

The Berlin Airport website read that "due to a technical issue at a system provider operating across Europe, there are longer waiting times at check-in."

Collins Aerospace said it was "actively working to resolve the issue and restore full functionality to our customers as quickly as possible".

The aviation tech company, which specialises in digital and data processing services, is a subsidiary of the American aerospace and defence group RTX, formerly known as Raytheon.

Cyberattacks and tech outages have disrupted airports around the world in recent years, from Japan to Germany, as air travel increasingly relies on online, interconnected systems.

Aviation expert Anita Mendiratta, who is also a special adviser to the secretary general of UN tourism, told AFP it was difficult to know who was behind the attack.

But she stressed it was "a disruption caused to a software not a specific airport" and it was important to try to "contain the contagion".

The aviation sector saw a 600 percent increase in cyberattacks from 2024 to 2025, according to a report by French aerospace company Thales released in June.

"From airlines and airports to navigation systems and suppliers, every link in the chain is vulnerable to attack," the report warned, pointing out that the strategically and economically important sector had become a "prime target" for cyberattacks.