Lufthansa has canceled more than 500 flights on Thursday after Verdi union called for strike action at six German airports over pay and job security. The strike will last for seven hours Thursday morning, between 5 a.m. and noon, local time.

Verdi, which represents 33,000 Lufthansa workers, is demanding a 5.2% pay increase over the next year as well as job security. Verdi said the strikes are meant to apply pressure to Lufthansa and act as a warning signal that talks over pay should continue Friday for workers at Lufthansa Cargo, Catering subsidiary LSG, Lufthansa Technik, Lufthansa Systems as well as Lufthansa ground staff and cabin crew.

Several German media outlets are reporting that Lufthansa will cancel nearly all domestic and Intra-European flights. The carrier said it will try to operate most of its intercontinental flights.

Lufthansa was not immediately available for comment.

According to Lufthansa’s website, its Frankfurt hub will be affected. In Berlin, Lufthansa flight attendants have also called a strike. Actions are also planned in Munich, Düsseldorf, Cologne and Norderstedt.