Lufthansa, Germany’s biggest airline, has been fined a record $4 million for discriminating against Jewish passengers, the US Department of Transportation announced Tuesday.

The fine stems from a May 2022 incident in which the airline prohibited 128 Jewish passengers from boarding. The DOT noted in a consent order that the passengers were wearing “distinctive garb typically worn by Orthodox Jewish men.” They were denied boarding as a group and were unable to connect in Frankfurt to Budapest from a New York flight because of “alleged misbehavior of a few.”

However, the passengers did not know each other nor were they traveling together.

In a press release, the airline said the incident “resulted from an unfortunate series of inaccurate communications, misinterpretations, and misjudgments throughout the decision-making process” and that these actions, “although regrettable, do not support any finding of discrimination and the department’s findings in this case.”

The misbehavior detailed in the report includes 60 passengers onboard “repeatedly disregarded” safety and public announcements from flight attendants and the flight deck. The crew said that some passengers obstructed flight attendants in economy class from its on-board food and beverage service, “inconvenienced other passengers” and argued with the crew about wearing masks.

The DOT said that Tuesday’s penalty is its largest ever issued by the federal agency for civil rights violations.

“No one should face discrimination when they travel, and today’s action sends a clear message to the airline industry that we are prepared to investigate and take action whenever passengers’ civil rights are violated,” said US Transportation Secretary Pete Buttigieg in the release.

Lufthansa said in a comment to CNN that following the “incident involving our Jewish passengers, Lufthansa has fully cooperated with the DOT throughout its review process.”

The airline added that its partnering with Jewish groups, like the American Jewish Committee to create training programs for its employees to “address antisemitism and discrimination.”

“Lufthansa is dedicated to being an ambassador of goodwill, tolerance, diversity, and acceptance,” an airline statement said.

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