American Airlines initiated a system-wide ground delay Tuesday afternoon owing to problems with its reservation system, likely leading to hundreds of canceled flights and thousands of stranded passengers.

“American's network system is experiencing intermittent outages,” the carrier said in a statement posted on its website.  “At this time, we are in a system-wide ground delay that will last until 4:00 p.m. CDT as we work to resolve this issue as quickly as we can.”

American said on its Twitter feed that “the issue is with our ability to access our res system.”