BRUSSELS — A cyberattack has targeted check-in and boarding systems, causing air traffic disruptions and delays at various major European airports, officials reported on Saturday.

Brussels airport stated that due to the attack, they could only use manual check-in and boarding processes, resulting in a “significant impact” on flight operations.

“A cyberattack on Friday night, September 19, targeted the service provider responsible for the check-in and boarding systems impacting several European airports, including Brussels Airport,” the statement read.

Authorities at Berlin’s Brandenburg Airport mentioned that their service provider for passenger handling systems was attacked on Friday evening, necessitating the disconnection of the systems by airport operators.

London Heathrow Airport, Europe’s busiest, said “a technical issue” affected a service provider for check-in and boarding systems.

Heathrow noted, “Collins Aerospace, which delivers check-in and boarding systems for numerous airlines at various airports globally, is facing a technical issue that might delay departing passengers.”

The airports advised travelers to check their flight status and apologized for any inconvenience.

Formed in 2018, Collins is a U.S. aviation and defense technology company and a subsidiary of RTX Corp., which was formerly Raytheon Technologies.

Collins equips passengers with the technology to perform self-check-in, print boarding passes and bag tags, and handle their own luggage through kiosks.

Collins said it was “aware of a cyber-related disruption” to its MUSE (Multi-User System Environment) software at “select airports” but that manual check-in operations could still be used.

“We are actively working to resolve the issue and restore full functionality to our customers as quickly as possible,” it said in a statement. “The impact is limited to electronic customer check-in and baggage drop and can be mitigated with manual check-in operations.”

The impact was felt only at some airports: the Roissy, Orly and Le Bourget airports in the Paris area reported no disruptions.