German carrier Lufthansa said Wednesday IT problems were forcing it to cancel and delay flights across its different airlines, in what appeared to be a major outage.

The company did not immediately specify which airports were affected but the departures board at its Frankfurt hub showed a slew of cancellations.

"Currently, the airlines of the Lufthansa Group are affected by an IT outage," the company tweeted.

"This is causing flight delays and cancellations. We regret the inconvenience this is causing our passengers."

Lufthansa is Europe's biggest airline group. It also owns Eurowings, Swiss, Brussels and Austrian Airlines.

"So far, we're not sure if Lufthansa (group) is the only one affected," a Lufthansa spokesman told AFP.

The group has assembled a crisis team that was racing to determine the cause and extent of the outage, he added.

Germany's Bild newspaper spoke of scenes of "chaos" at Frankfurt and Munich airport, reporting trouble with the check-in and boarding systems.