CHICAGO (WLS) -- Flight operations at Midway Airport are limited Wednesday morning after at least three technicians in the air traffic control tested positive on Tuesday
As of 11:35 a.m., 323 flights have been canceled at the airport after the air control tower had to be shut down after three technicians tested positive for COVID-19.
The FAA put a ground delay program in place, flights were operating on a "one-in-one-out" basis.
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The control tower had been cleared. The air traffic system has multiple backups in place to continue operations at the airport.
"In extreme circumstances, service levels could vary, but safety will not be compromised," the FAA said.
In response to the shut down, Southwest Airlines suspended all their flights in and out of the airport.
"We ceased operations at the Chicago Midway airport due to the closure of an FAA ATC tower in the Chicago area, impacting all airlines who operate at the airport," a Southwest spokesperosn said. "The disruption resulted in more than 50 Southwest flight cancellations today. We refer you to the FAA for additional information. We're offering flexible accommodations for all impacted Customers. We always encourage Customers to check Southwest.com for travel notifications and flight status."
Midway Control Tower workers test positive for coronavirus; hundreds of flights canceled at airport