Pradeep is a native of Darbhanga district. He was arrested from Badhaiya area of the state's Lakhi Sarai district, confirmed Bihar DGP Abhyanand Monday morning.
While Manoj Kumar, the prime accused was held from the state's Mujaffarpur district Saturday, as he was hiding in his in-laws' house, Pradeep was hiding at his maternal uncle's house from where the police arrested him.
The police will produce him in the local court for transit-remand, the official added.
Manoj Kumar was sent to judicial custody Sunday till May 4 following his two-day interrogation by Delhi police. He had revealed about Pradeep's presence in the brutality with the girl child at their house in Delhi.