CHICAGO (WLS) -- The air traffic control tower at Midway Airport has re-opened.
It has been closed for six days after three technicians tested positive for COVID-19 last week.
RELATED: Midway Control Tower workers test positive for coronavirus; hundreds of flights canceled at airport
Flight operations were limited during the closure and the Federal Aviation Administration said they put a ground delay program in place allowing flights to operate on a "one-in-one-out" basis.
The FAA said the tower has been thoroughly cleaned and other workers are still being evaluated.
RELATED: Southwest reduces service to and from Midway
Southwest Airlines, which has the most flights into and out of Midway, had greatly reduced its schedule while the tower was closed.
Midway Airport air traffic control tower reopens after workers test positive for COVID-19