The head of the South Korean clothing factory in southeastern Bangladesh that saw violent protests over the weekend says the protests were organized by an unidentified group of people that do not work for the factory.

Seong Ki-hak of the garment manufacturer ‘Youngone’ said Monday that it has yet to be determined who is behind the violent protests that were launched simultaneously at seven of the Youngone factories over the weekend. He said the assailants who were at the center of the rally were from another region and that the rallies were well-organized.

The Korean firm met with its local laborers on Saturday to narrow differences over workers’ complaints over wages. During the talks, the Korean company agreed to the laborers’ salary demands, saying that related changes will take effect next month. Soon after, laborers returned to their workplace.

However, according to Youngone, later that day, unidentified assailants who were not laborers of the Korean firm staged violent protests at seven of the firm’s factories and destroyed machinery, equipment and vehicles.