CHICAGO -- There are delays for Southwest Airlines flights at Midway Airport due to what the airline is calling "issues with our systems."
A spokeswoman for Midway said there are delays of about 30 minutes right now.
There have also been reports on Twitter of travelers at other airports who say they are grounded and waiting to take off.
The airline's airport kiosks and web site were not available for check-in or booking.
Some passengers reported that Southwest was in the process of issuing hand-written paper tickets to get fliers back in the air.
The airline says it is "working hard" to fix the issues.
This is a developing story. Please check back for more details.