By Leada Gore
Power has been restored at Atlanta's Hartsfield-Jackson International Airport, city officials announced late Sunday night.
Power went out at the world's busiest airport around 1 p.m. ET on Sunday, leading to the cancellation of thousands of flights and delays for hundreds more. Passengers were left stranded as the FAA put a ground stop in place, slowing or halting inbound air traffic. Cell service and WiFi were also impacted, making passenger communications difficult.
Delta, which has its major hub at Hartsfield, advised travelers headed to Atlanta on Monday to check their flight status as 300 flights have already been cancelled due to the outage.
Georgia Power said power was restored for all essential operations as of 11:45 p.m. ET Sunday.
Atlanta Mayor Kasim Reed said the power outage was caused by a fire in an underground tunnel that knocked out the main power source and the airport's backup system.
Georgia Power officials said they believe the fire was caused one of its switchgears in an underground electrical facility that failed and sparked a blaze.
"The fire was located adjacent to redundant circuit cables and switching mechanisms serving the airport and those cabled were damaged, resulting in the outage and loss of redundant service methods," Georgia Power said in a written statement.
The fire impacted the underground facilities and the substations serving the airport.
Reed said the city opened its convention center to accommodate people affected by flight cancellations and Chick-Fil-A fed stranded travelers. The airport is also offering free parking through 8 a.m. Monday for those affected by the outage.
Atlanta's airport serves more than 275,000 passengers a day on as many as 2,500 flights.
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