The victim has not been identified by the police.
A case has been lodged against the unidentified people who lynched him, an official said.
In rural Bihar, street 'justice' is becoming increasingly common. Over 50 cases of lynching were reported from the state over the last four months.
In one of the worst cases of lynching in Bihar, 10 people from the underprivileged Kueri community were thrashed to death in Vaishali district over an alleged theft in September 2007. Later, a high-level probe found that the men were not thieves as the villagers had suspected.