The group raided the house of the man at Barieya village last night shortly after the carcass of a cow was allegedly found, they said.
The police rescued the man from the marauding mob and admitted him to a local hospital, but later shifted him to a hospital in Dhanbad owing to the seriousness of his injuries, the police said.
The man was out of danger, they said, adding that some persons were also injured in the clash between the mob and the police.
Ten persons have been detained and prohibitory orders under Section 144 of the CrPC imposed in the area, Deputy Inspector General of Police Bhimsen Tuti told PTI.
Jharkhand Inspector General of Police (Headquarters) Ashish Batra said the matter was under investigation and a case has been registered at Deori police station.