Angry workers on Monday threw stones at factories, smashed vehicles and blocked a major highway in the area. Some 200 factories were closed for the day after the protest erupted in Savar, the industrial zone where Saturday's deadly fire occurred.
Officials say many workers were trapped in the eight-story building, which lacked emergency exits. Firefighters have pulled out at least 100 bodies, and 12 more people died at hospitals after jumping from the building.
Unions in Bangladesh have long complained about unsafe factories where workers work in dismal sweatshop conditions.