US authorities have imposed a record $4 million penalty on Lufthansa after discovering that the airline discriminated against over 100 Jewish travelers by preventing them from boarding a flight in 2022, officials announced on Tuesday.

The 128 passengers were denied boarding for a connecting flight after some failed to comply with instructions, including anti-Covid mask requirements, on a flight from the United States to Germany, according to US transport authorities. Lufthansa did not immediately respond to an AFP request for comment.

The US Department of Transportation stated that the penalty for the boarding refusal on May 3, 2022, in Frankfurt, was the largest it had issued for a civil rights violation. The travelers, who wore distinctive clothing such as black hats and jackets, informed investigators that they were treated as a single group despite many not traveling together and not knowing each other.

Lufthansa denied boarding 'to everyone for the apparent misbehavior of a few, because they were openly and visibly Jewish,' DOT authorities noted in a filing. The issue arose when the captain of the initial flight reported to Lufthansa security that some passengers were not adhering to rules, including mask-wearing during the trip and not congregating in aisles or near emergency exits.

DOT authorities received more than 40 discrimination complaints from Jewish passengers in this instance. Lufthansa informed DOT that it has publicly apologized multiple times for barring the passengers from continuing their journeys but denied any suggestion that its employees engaged in any form of discrimination.