On 9 August, a joint team of the West Bengal CID and Bihar police arrested the kingpin of the racket in connection with the Bihar intermediate exam scam.
Acting on a tip off from those arrested in the case, the joint team arrested absconding Vikash Kumar (39) from Jinjinjirabajar area in South 24 Parganas district.
According to DIG CID (Operations) Dilip Adak, Kumar, who was a clerk-cum-storekeeper of the Bihar Vidyalaya Pariksha Samiti was in-charge of the whole gang.
"He used to take around Rs five to ten lakh from each students for changing their answer sheets. This he was doing in a very innovative manner," Adak said, adding the Bihar police had approached them to help in nabbing the culprit.
The tender of printing question papers and blank answer sheets for exams conducted by the Samiti, were given to a Mathura-based press cancelling the earlier order given to a Gujarat-headquartered company.
Kumar had sent a letter asking the Gujarat company to print blank answer sheets and received 28 lorries of them, Adak said.
He then, when contacted by parents as well as candidates, used to provide them with blank answer sheets.
"And after they fill up the answers, Kumar used to replace their original answer sheet with this one," the officer said.
Kumar's name surfaced after the Gujarat-based printing press lodged a complaint with the Bihar police when their bills shot up close to Rs nine crore.
Kumar, a resident of Bihar's Patliputra, had recently bought a flat at Kolkata's Phoolbagan area spending nearly a crore.