Unionized delivery workers staged a sit-in on Monday night, calling for the implementation of an agreement on sorting parcels. 

More than 100 delivery workers held the sit-in throughout the night at the Korea Post building in Yeouido, Seoul.

The union workers accused Korea Post of making false claims that it paid them fees for sorting parcels. They then called for the implementation of a previous agreement that logistics companies will take responsibility for sorting packages before delivery.

Korea Post said it had explained revisions to fees for sorting parcels last year during meetings with the union before finalizing the new fees. 

Meanwhile, unionized delivery workers plan to hold a massive rally on Tuesday near the National Assembly.