Flight cancellations at Hamburg Airport after a surprise strike by workers affected more than 40,000 passengers on Sunday, a day before a planned wider protest across Germany amid new contract negotiations.

The airport in Germany’s second largest city said the one-day strike, called over pay and conditions, began earlier than expected “without any notice.”

Nearly 300 flights were cancelled at Hamburg airport on Sunday as ground handlers walked out ahead of wider strikes planned across Germany on Monday. German trade union Verdi had not given notice of the move,