United Airlines system outage causes ground stop

United Airlines appeared to have issued a systemwide ground stop on Tuesday, causing possible disruption to flights across its network.

An advisory issued by the Federal Aviation Administration said that the airline had requested a ground stop due to an equipment outage.

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In a statement, United said that all airborne planes would continue to their destinations and cited a “technology issue.”

Transportation Secretary Pete Buttigieg said in a Tweet that his department was monitoring the issue and would “make sure UA meets its obligations to affected passengers.”

It was not immediately clear what technology system was affected, nor when things could be expected to return to normal. Subsequent bulletins posted by the FAA suggested that the issue affected communications between flight crews and United dispatchers.

The issue comes the day after Labor Day, the unofficial end of the summer travel season in the U.S., and months after United suffered an operational meltdown following several severe thunderstorms, leading to thousands of flight cancellations and delays.

This is a developing story. Check back for updates.