Faulty equipment blamed by Trump administration for FAA ground stop. Follow for live updates.

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Faulty equipment in an “incredibly old” telecommunication system may have caused an air traffic control issue, U.S. Transportation Secretary Sean Duffy says.

In a press briefing on Saturday, he said a contractor was doing routine maintenance to upgrade copper wire to fibre optic cable when something went wrong.

Officials are now investigating whether the error was due to “incompetence” or a “faulty router,” he added.

U.S. officials said on Saturday that the effects of the stop could be felt for days, adding that the system will likely be operating normally in time for the U.S. Thanksgiving travel rush.

This is just the second nationwide ground stop in the United States since the Sept. 11, 2001, attacks.

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