ABC News now puts the number of US flights cancelled during the FAA ground stop at more than 4,000, more than double the last FlightAware count.
The broadcaster's live blog says:
More than 4,000 flights have been canceled amid the issue
ABC News does not name a data provider for the figure, or say what time it was recorded or what period it covers. It has not been independently checked.
The most recent FlightAware figures, reported by ABC7 San Francisco as of 6.04pm ET on Friday 13 November, showed 1,913 cancellations and 10,494 delays. Flightradar24 has put cancellations at more than 1,000.
Because ABC News gives no source or timestamp, it is not possible to say whether the higher figure reflects a later count, a different way of measuring, or both.
The same ABC News page carries the headline "Some flights taking off, no indication of nefarious act".