MADRID (AP) — Spanish train workers have begun a nationwide strike as one of the country’s busiest holiday periods kicks off.

Workers for the state train company Renfe and rail infrastructure firm Adif began the strike Thursday to protest staff shortages and company plans to privatize certain operations.

Renfe said a quarter of some 2,000 scheduled trains will be canceled in the two-day stoppage but government-imposed minimum services of up to 77 percent in intercity and bullet train routes meant the strike was not likely to provoke chaos.

Renfe also allowed passengers to change their tickets free of charge, and bus companies were reported to be putting on extra services.

The stoppage comes as people travel for their summer holidays in August, one of the country’s busiest vacation periods.

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