Patna, June 23 (IANS): With the Central Bureau of Investigation (CBI) registering an FIR in the NEET question paper leak matter on the basis of the report of the Bihar Economic Offences Unit (EOU), sources claimed that officials involved in the probe suspect that the question paper was leaked from one 'Oasis School' in Jharkhand's Hazaribagh district.

According to an EOU source, a question paper with a booklet number (6136488) was purportedly shared on the WhatsApp group of the 'examination mafia' in Patna. The booklet was received by that school in Hazaribagh.

During the investigation, it also appeared that the box in which the booklet reached the school was also found tampered with.

The CBI is now trying to learn whether the question paper was leaked while it was being moved to the bank, or was stolen somewhere mid-route between the bank and the examination centre.

According to a source, Sanjeev Mukhiya, an employee of Nursarai Udyan College, Nalanda, was the kingpin of the 'paper leak gang'.

He has been allegedly conspiring with his associates to leak the NEET exam paper for the last several months.

Before the exam, according to sources, a professor had sent the paper to Sanjeev Mukhiya on WhatsApp. The paper was then made to solve by PG medical students from Patna and Ranchi.

After solving all the questions, it was sent to Chintu Kumar a.k.a. Baldev (on his cellphone) at Karayparsurai block in Nalanda district.

The Bihar EOU also came across a list of select candidates who were given the paper before the exam, and made to memorise the answers.

The EOU has so far arrested 13 people involved in connection with the matter. Besides, many others are being questioned.

Besides, the Special Investigation Team (SIT) of EOU has conducted raids at Deoghar in Jharkhand and arrested six persons including Chintu Kumar -- said to be a relative of the kingpin, Sanjeev Mukhiya.

According to sources, the EOU has also identified the PG medical students who solved the NEET exam paper, and 10 students from medical colleges in Patna and Ranchi are under its scanner.

The SIT learnt about the role of PG medical students on the basis of some WhatsApp chats with the accused individuals.

The accused allegedly sent the question papers to the students on their mobile phones.

Earlier, the CBI registered the FIR on Saturday night and has started the investigation.

The Education Ministry had summoned Nayyar Hasnain Khan, Additional Director General of Bihar's EOU, and sought information related to the paper leak.

On Saturday, Khan met Union Education Minister Dharmendra Pradhan in Delhi and submitted the probe reports before him.

Following the recommendation of the Central government, the CBI registered the case on Saturday night.

The NEET examination was held on May 5 and its question paper was made available to the 'education mafia' a day earlier, on May 4.