A man died on Thursday after being tortured in an iron cage by his father and stepmother in Narayanganj's Fatullah.
The deceased was identified as Hemayet Hossain Sumon, 35, son of Habibullah of South Rasulpur.
Police rescued the deceased's brother, Safayet Hossain Raju, from the cage.
Sub-Inspector of Fatullah Model Police Station Fazlul Haque said, "No injury marks were found on Sumon's body. We have sent the body to hospital for autopsy."
Further steps will be taken after receiving the autopsy report, he added.
Officer-in-Charge of the police station Md Aslam Hossain confirmed that the disabled brothers would be confined to the house because they had gone missing several times prior.
The deceased's father also claimed the same.
However, Raju said they were held in confinement over property disputes.
Police filed an unnatural death case in this connection.