The workers approached the police yesterday evening and filed a complaint with the Shahaj Nagar police station here.
According to the complaint, the workers of a brick kiln in Dundai village were picked up on January 19 by the owner's henchmen and were kept inside a building with men and women in two separate rooms.
The brick kiln owner along with the labour contractor and three others sexually assaulted the eight women and released them on January 20 after threatening them of dire consequences if they approached the police, the police said.
A case has been registered against the brick kiln owner and others under relevant sections of the IPC.