Thousands of subway workers in Seoul and three other major cities have entered their second day of strikes, with union workers and management failing to work out a compromise over the five-day workweek system.

On the first day of the walkout Wednesday, the operation of subway services was carried out relatively smoothly as city officials swiftly mobilized non-union workers to minimize public inconvenience in Seoul, Daegu, Busan, and Incheon.

As union workers continued to stage strikes for the second day, the management of the subway corporations of Seoul and Incheon called on the unionists to immediately get back to work by noon Thursday. Subway corporation officials also fired 36 leading union figures and brought charges against some 50 employees for violating labor union-related laws.

Union workers, on their part, vowed to continue the strike until their demands are met. Unionists are calling for the additional employment of some 6,000 workers in order to implement the five-day workweek without any deterioration to present working conditions.

The management, on the other hand, is insisting that the current number of employees is sufficient to carry out a five-day working week. The five-day workweek system took effect at the beginning of the month.