He had beaten his mother Saturday when she went to see him in the hospital.
The district police authorities were informed about the incident. A group of policemen then reached the hospital, tied Thakur's hands and legs with a rope and started beating him with a cane, police said.
The Jharkhand police headquarters has sought a report on the incident from Dumka Superintendent of Police A.K. Singh.
According to police, Thakur will be shifted to a mental hospital of Ranchi.
Dumka is some 450 km from Ranchi.