Alaska Airlines said on Friday it has banned 14 passengers from future travel with the carrier after what it called “unacceptable” behavior on a flight from Washington Dulles to Seattle.

U.S airlines and law enforcement agencies bolstered security at Washington-area airports after reports of “mob behavior” by supporters of President Donald Trump on flights into the region before Wednesday’s siege on the U.S. Capitol,” raising concern about their departure.

Seattle-based Alaska said a number of passengers on a flight out of Washington late Thursday “were non-mask compliant, rowdy, argumentative and harassed our crew members.”

“Because of their actions and non-compliance, we have banned 14 of those passengers from future travel with us,” the airline said in a statement.

The union representing American Airlines’ flight attendants, the Association of Professional Flight Attendants (APFA), also raised alarm about passengers “exhibiting politically motivated aggression towards other passengers and crew” on flights this week.

“To say I am worried about our Flight Attendants’ safety is an understatement,” APFA President Julie Hedrick said in a statement. “This behavior is dangerous and threatening.”

APFA is working with other flight attendant unions, lawmakers, and regulatory agencies in Washington, D.C. to enhance safety and make sure that “anyone displaying threatening or abusive behavior will not be allowed to board our aircraft now or in the future,” she said. (Reporting by Tracy Rucinski and David Shepardson; editing by Jonathan Oatis and David Gregorio)

This article was written by David Shepardson and Tracy Rucinski from Reuters and was legally licensed through the Industry Dive publisher network. Please direct all licensing questions to legal@industrydive.com.

Photo Credit: Alaska Airlines is clamping down on passengers getting rowdy and disrespectful after the pro-Trump riot in D.C.