Ground staff at Lufthansa airline walked out at major airports on Wednesday in a dispute over pay, causing major disruption to travel.
Germany's national carrier Lufthansa said it expects "extensive effects" on its flight programme on February 7 and 8 as a result of the strike, impacting an estimated 100,000 passengers.
The Ver.di union said its members in Frankfurt, Munich, Hamburg, Berlin, and Duesseldorf airports began striking at 4am (3am GMT).
The union is seeking a 12.5% pay raise, or at least an extra 500 euros per month, in negotiations for nearly 25,000 employees, including check-in, aircraft handling, maintenance and freight staff.
Lufthansa said it is working on a special timetable and criticised the scale of the strike early in the dispute.
Coinciding contract negotiations in the rail, air, and local transport sectors have caused several weeks of disruption for travelers and commuters in Germany.
Last Thursday, Ver.di called security workers at most of Germany’s major airports out on a one-day strike that prompted widespread flight cancellations.
On Friday, it staged a walkout that led to local buses, trams and subway trains being canceled in much of Germany.
Several-hour or one-day “warning strikes” are a common tactic in German contract negotiations.
Passengers with flights booked on these dates will be informed of cancellations and rebooking options from Monday via email or the Lufthansa app, the airline said.
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