Samsung Electronics workers in South Korea say they're now on an indefinite strike, days after thousands walked off the job. 

More than 6,000 unionized workers with the chip-maker's semiconductor division walked out on July 8, according to The New York Times, as part of a months-long dispute over wages and vacation days. Two days later, leaders with the National Samsung Electronics Union (NSEU) called on their 31,000 members to join the work stoppage indefinitely.

The NSEU is demanding a 3.5% wage increase, an extra paid vacation day, a bonus structure that rewards workers and executives more equitably, and compensation for lost wages from the ongoing strike. The union previously conducted a one-day walkout in June, marking the first labor strike in Samsung Electronics' history. 

Samsung is the world's largest memory chip manufacturer for computers and other electronic products. Although the union says that its three-day walkout has slowed operations, the company claims that production has not been affected, and that it is "committed to engaging in good faith negotiations with the union."