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Air travelers call the airlines a lot of names. Maybe it was just a matter of time before the airlines struck back.

At least, that seems to be the case with Ryanair. The outspoken - and at times outlandish - CEO of the European low-cost carrier called one of its passengers "stupid," according to The Telegraph.

On August 15, Suzy McLeod of Berkshire, England, was charged 300 euro for failing to print her own boarding passes - five in total for her family - for their flight from Alicante, Spain, to Bristol, England. The airline charges 60 euro to "re-issue" a boarding pass at the airport.

McLeod reportedly took to the airline's Facebook to complain and garnered support in the form of "likes" from over half a million Facebook users. The post is no longer visible on the company's Facebook page.

But Michael O'Leary, Ryanair's CEO, struck back. "We think Mrs. McLeod should pay 60 euros for being so stupid," he said. "She wasn't able to print her boarding card because, as you know, there are no internet cafes in Alicante, no hotels where they could print them out for you, and you couldn't get to a fax machine so some friend at home can print them and fax them to you," the Telegraph reported.

He went on to say that 99.98 per cent of Ryanair passengers print their boarding passes in advance. "To those who don't, we say quite politely: 'B***** off'".

On August 21, the airline said in a statement to The Telegraph, "As is clearly outlined in the terms and conditions for every Ryanair passenger, Mrs. McLeod agreed at the time of booking that she and her fellow passengers would check in online and print their boarding cards before arriving at their departure airport, and she also accepted and agreed that if she failed to do so then she would pay our boarding card re-issue penalty of £60 [60 euros in the EU zone] per passenger."

The airline, famous for its ultra-low fares and its fees, has in the past said it was exploring options for charging passengers a fee to use the bathroom and for creating a " standing room only" section on its aircraft.

Attempts by ABC News to reach Ryanair and Suzy McLeod were not successful.