(VOVworld) - A union representing German train drivers called its members out on a four-day strike Tuesday, escalating a bitter contract dispute with the national railway operator.

Train drivers are seeking a 5% pay increase and shorter working hours (Photo: Getty Image)

The GDL union said the strike will run from early morning Thursday to Monday morning, with freight train drivers starting the strike on Wednesday afternoon. This follows a series of shorter strikes, including a two-day walkout last month. The union is protesting tough stance by national railway Deutsche Bahn in response to drivers’ demands for a 5 percent salary increase and a reduction of working hours to 37 hours per week.