On Sunday, Kumho Tire announced it would shutdown operations at three of its plants following ongoing labor disputes. The following day riot police were called as unionized workers protested the lockouts at Kumho’s plant in the Gwangsan District, Gwangju.

The union demanded Kumho cancel its lockout immediately and said the rally would continue until their demands are met, according to local media. Kumho said the lockout wouldn’t be withdrawn unless the strike stopped.

The tiremaker shutdown production at its factories in an effort to “minimize the additional loss and to protect employees who do not join the strike alongside the factory facilities,” it said in a press release. Roughly 3,000 of its 3,400 workers have joined the union.

The strike started on Aug. 17 when management and labor could not agree on a peak wage system. To date, sales lost due to the strike are around $78,501,280 (94 billion won), Kumho said.

“If the overall strike of the labor union continues, it will bring about huge losses and damage to the company as well as partners,” Kumho said in a press release.

During its most recent negotiation management presented a 4.6% pay increase of 2,950 won a day, a wage peak system from 2016, a lump sum allowance of 3 million won for the wage peak system and an increase in loans for non-homeowners, according to media. The union agreed to the delayed peak wage system but none of the additional suggestions.