PATNA, Sept. 4 -- Competitive examinations paper leak mafia Sanjiv Singh alias Lutan Mukhiya was sent back to the Beur Central Jail on Thursday after being grilled by a team of economic offence unit (EOU) of the Bihar police, officials said. Mukhiya was taken on 24-hour remand in connection with the alleged tampering of NEET 2017 paper case. A case was registered against five persons, including Lutan Mukhiya's son Dr Shiv Kumar, on July 7, 2017 at Patrakar Nagar police station under sections of cheating, forgery and IT Act. In June last year, the EOU took over the investigation into the case. According to officers aware of the investigation, the focus of Mukhiya's questioning was to determine how cheaters obtained the question papers being delivered to examination centres by breaking into the system. Officers said that the EOU sleuths asked Mukhiya Sources said the EOU sleuths questioned Mukhiya about his actual role in the 2017 NEET case and any connection between old cases and the solver network. The network functions by sending proxies in place of real candidates to the examination halls after taking hefty amounts from the candidates. EOU sources said they received some leads and information during Mukhiya's interrogation, and the subsequent investigation will relate to cases of malpractices and paper leaks in various competitive examinations. According to earlier EOU investigation, the question leak was carried out through a well-hatched plan to lay hands on the sealed questions during their transit from the printing press, scan them through specialised tools and then hand them over to their clients for hefty monetary consideration. Mukhia, according to investigation done earlier, had worked at several levels in nexus with criminals and politicians and kept evading arrests due to such proximity to power....