Shankar Lal had gone to Dataramgarh Police Station with his son who was called for interrogation in a theft case when he got unconscious and collapsed near a pole in its premises, police said.
He was taken to a nearby hospital where he died, SHO Dataramgarh Sayar Singh said.
Heart attack could be the probable reason behind the death and the matter was being investigated, SP Sikar Haidar Ali said.
Family members and relatives of the deceased have brought the body from the hospital to the police station before the post-mortem could be done and are protesting there, police said.