The man escaped and filed a complaint with the Titawi Police Station, following which the unit's owner, Rajkumar, was arrested yesterday, SHO Bhanupratap Singh said.
The complainant alleged that he was tied with chains for four days, the officer said.
He said the victim, who earlier worked at an eatery, was sold to Rajkumar.
Rajkumar and three others have been booked under Section 342 (Punishment for wrongful confinement) of IPC and the matter is being investigated, the SHO said.