United Airlines said Saturday that some cockpit door access information may have been made public, but said that it has measures in place to keep the flight decks on its aircraft secure.
The airline did not say how the information became public, but said "we are working to resolve this issue as soon as possible."
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United Airlines spokesperson Maddie King said "I can confirm it was not a breach," like a hack, but did not give more information, saying the company does not discuss security procedures.
King later said in an emailed statement to NBC Los Angeles that "the information was inadvertently made public."
"The safety of our customers and crew is our top priority and United utilizes a number of measures to keep our flight decks secure beyond door access information. In the interim this protocol ensures our cockpits remain secure," King said in a statement.
United's network serves 215 domestic airports and 122 international destinations and has nearly 4,500 daily departures, according to United's website.