“Fauji Pandey was arrested with arms from a construction site by a special police team on Wednesday night,” a district police official said.
The arrest took place four years after Brahmeshwar Singh was shot dead in Ara town while on a morning walk.
Fauji was carrying a reward of Rs.50,000 on his head and faced over a dozen criminal charges including those of murder, extortion and abduction.
“We will interrogate Fauji to know more about motive behind the killing and other people’s involvement,” a police officer said.
Brahmeshwar Singh founded the Ranvir Sena, an upper caste private militia that had been blamed for many killings, mainly the poor.
The police had filed a chargesheet against six people for the murder.