Passengers face further cancellations as US flights slowly resume after ground stop

While flights in the United States started resuming on Saturday following the longest nationwide ground stop in 25 years, more than 2,000 flights have been cancelled as airlines work to return to normal operations. Nearly 6,000 flights were cancelled on Friday, with the incident marking only the second time an alert to ground all flights had been issued in US airspace since the 9/11 attacks.