BRUSSELS (AP) — A cyberattack targeting check-in and boarding systems has snarled air traffic and caused delays at some of Europe’s top airports, officials said Saturday.

The Brussels airport says the attack means that only manual check-in and boarding was possible there, and the incident was having a “large impact” on flight schedules.

“There was a cyberattack on Friday night 19 September against the service provider for the check-in and boarding systems affecting several European airports including Brussels Airport,” it said in a statement.

Authorities at Berlin’s Brandenburg Airport said a service provider for passenger handling systems was attacked on Friday evening, prompting airport operators to cut off connections to the systems.

London Heathrow Airport, Europe’s busiest, said “

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