An alleged cyberattack targeting a company that manages check-in and boarding systems for airlines caused delays and cancellations at Europe’s busiest airports on Saturday.
Passengers were left stranded at Heathrow, Brussels, and Berlin airports following the reported cyberattack on Collins Aerospace, an American aviation company headquartered in North Carolina.
RTX, the parent company of Collins Aerospace, told TIME in a statement that it had become “aware of a cyber-related disruption” to its MUSE software in “select airports”.
“We are actively working to resolve the issue and restore full functionality to our customers as quickly as possible,” it added.
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Brussels Airport said a “cyber attack” on Friday evening was affecting several European airports. It added that only manual check-in and boarding were possible and that the attack had “a large impact on the flight schedule and will unfortunately cause delays and cancellations.”
Heathrow Airport, Europe’s busiest, said that Collins Aerospace “is experiencing a technical issue that may cause delays for departing passengers.”
Berlin Airport said on its website that there were longer waiting times at check-in “due to a technical issue at a system provider operating across Europe.”
United Airlines said the issue was “causing minor departure delays,” and Delta said it expected minimal impact to flights from the three impacted airports.
Passengers stuck at the airports reported long delays on Saturday and said they had received little information regarding the reported attack.