Hundreds of flights have been cancelled at Toronto’s two airports after the U.S. Federal Aviation Administration issued a ground stop order on Friday, leaving many passengers scrambling. The Greater Toronto Airports Authority, which operates Toronto Pearson International Airport, said in a statement that there were no scheduled U.S.-bound departures or arrivals at this time “Passengers are advised to check directly with their airline for the latest flight information before heading to the airport.” The GTAA noted that international and domestic flights that do not require transit through the U.S. airspace will continue to operate. “We are increasing staffing across the airport to assist affected passengers. Our support teams are being deployed throughout the terminals, with additional resources available in the U.S. departures area,” the GTAA said in a post on social media. “We are also working closely with airlines and have implemented a parking plan for aircraft.” According to the U.S. FAA, the ground stop order issued around 3:54 p.m. ET was due to communications problems at regional air traffic control centres. NAV Canada, the country’s air navigation service provider, said it briefly implemented “traffic management measures” at Pearson and three other major airports “to safely manage traffic volumes.” NAV Canada has said that the U.S. ground stop has no impact on its operations and systems are operating normally. According to Pearson’s website, there are 50 departing flights to the U.S. that have been cancelled, while 59 American flights will not be arriving in Toronto as scheduled. CP24 spoke to several passengers at the airport who were frustrated about what’s happening. Donna, who is flying to New York City for the weekend, said her flight has been rescheduled for tomorrow. “I was really hoping to fly out tonight. So, it’s a bit of an unfortunate situation,” she told CP24. “Definitely very disappointed that my plans for the weekend have been cancelled, or at least very delayed.” Derek is supposed to fly to Las Vegas and says Air Canada has told him to “stick around.” However, he is not optimistic that he’ll get to his destination. “It’s most likely going to be cancelled. And even if you’re rebooked till tomorrow, it’s unlikely. So, I think you’re going to have people with a lot of refunds,” Derek said. Shahab Mirmiran came to Toronto on Monday for work and is hoping to get back to Los Angeles tonight. “Unfortunately, we don’t know what’s going on. I have to go. I need to do something for work,” he said. “They’re just saying you have to wait.” Another man who arrived from London, U.K., says he’s waiting to hear about his connecting flight to Raleigh, N.C. “It stinks, but just holding off for a little bit and seeing what happens,” he said. An Air Canada spokesperson said flights to and from the Caribbean and South America may also be affected. “Any flights currently airborne have been advised they are permitted to continue,” the spokesperson said. “We are monitoring the situation very closely and will provide updates as they become available.” Meanwhile, Toronto Billy Bishop Airport said it was monitoring the situation in co-ordination with airline and air traffic control partners. The island airport noted that Air Canada and Porter Airlines have cancelled all remaining Friday U.S.-inbound and outbound flights. With files from CP24 reporter Natalie Van Rooy and The Canadian Press