Dozens of workers at a Foxconn plant in Chengdu, China were arrested this week after a clash with security staff, according to a report.

Taiwan-based Want China Times (WCT) reported that the clash broke out on Monday night at a male dormitory for Foxconn workers. Security guards had attempted to stop a thief, when several employees with grudges against the officers forced them away.

The situation rapidly escalated, and up to 1,000 workers eventually joined in, WCT reported. Workers threw trash bins, chairs, pots, bottles, and even fireworks from the upper floors of the building, destroying public facilitates.

The riot ended after two hours, after dorm administrators reported the case to local police and hundreds of officers arrived at the scene to suppress the violence. Dozens were arrested.