Lufthansa Group on Wednesday paused all departures and landings at its hub in Frankfurt due to an IT failure.
The outage was caused by a telecommunications line failure in the Frankfurt area, the company said. The outage also caused a partial shutdown of Lufthansa's Munich operation.
Lufthansa Group airlines are Lufthansa, Swiss, Austrian, Brussels, Edelweiss, Eurowings and Air Dolomiti.
Lufthansa said it will rebook canceled flights free of charge and automatically inform customers via their mobile phones. However, the technology failure could delay some of those messages from being sent.
"If you do not receive a message from Lufthansa, please check the current status of your booking," the company's website reads.
The IT failure occurred two days before more anticipated widespread disruptions in the Lufthansa network due to a planned strike by the union that represents its ground staff. The Feb. 17 action will happen in Frankfurt and Munich among other German airports.
Lufthansa said it will announce proactive cancellations related to the strike.