More than a dozen United Airlines flight attendants who were fired for their insistence on additional screening measures after discovering "menacing" graffiti scrawled on an airplane have filed a federal complaint against their former employer.

The Los Angeles Times reports: "On July 14, 2014, United crews departing from San Francisco International Airport bound for Hong Kong found the words 'BYE BYE' in six-inch high letters alongside two faces, one smiling and the other one also smiling, but with eye brows drawn in a more sinister expression. The writing was traced in an oil slick from the auxiliary engine in the [Boeing 747] aircraft's tail cone. "

The 13 flight attendants have filed a federal whistleblower complaint with the Department of Labor. They say they found the drawing "menacing" and "devilish" and that they requested that more than 300 passengers aboard the July 14 flight be taken off for an additional security sweep.

Reuters says:

"The flight attendants, all with 18 or more years of experience, said the airline refused to deplane the passengers and conduct a security inspection. They said they disobeyed orders to work, believing the lives of more than 300 passengers and crew on the jumbo jet could be endangered."After a delay, the July 14 flight was eventually canceled. United accused the flight attendants of insubordination and fired them all, according to the complaint."

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