A CBI team from Delhi reached the office of the Economic Offences Unit (EOU) of the Bihar Police in Patna on Monday morning in connection with its investigation into the allegations of irregularities in medical entrance exam NEET-UG, officials said.

The EOU, which had been investigating the matter until the Centre ordered a probe by the CBI, has arrested 18 people in connection with the case, they said.

"The CBI officers are collecting evidence related to the case from the EOU," an official said.

The CBI had on Sunday filed an FIR in connection with the alleged irregularities in NEET-UG, which was held on May 5, on a reference from the Education Ministry, amid countrywide protests and litigations by students.

"The evidence collected by the EOU during the course of investigation include pieces of the burnt question paper recovered from a house in Patna, mobile phones of those arrested, SIM cards, laptops, post-dated cheques and reference questions papers provided by the National Testing Agency (NTA)," an EOU officer said.

"All those arrested are in judicial custody in Patna, and the CBI team may take them to Delhi for detailed interrogation by obtaining transit remand from a court here," he said.

The CBI is also likely to file multiple FIRs in connection with the matter to probe the destruction of evidence, and also register disproportionate assets (DA) cases against some of those accused who are public servants, he said.

"A DA case may be registered against arrested accused Sikander Prasad Yadvendu, a junior engineer in Danapur Town Council, as he reportedly acquired huge assets that are disproportionate to his known source of income," the officer said.

Yadvendu, originally from Samastipur, has been identified as the prime suspect in the case, he said.

"He has a history of involvement in criminal activities. Before becoming a junior engineer in 2012, he worked as a contractor in Ranchi. He was previously implicated in an LED scam worth Rs 3 crore. He has served a jail sentence for his role in that case," the officer said.

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