Summoned to CBI as an accused, Gupta, a 1971 batch IAS officer, faced many questions about the allocation of coal blocks to some selected companies during his stint as the secretary in the ministry, official sources said.
The government had initially refused to grant permission to CBI to question Gupta, a bureaucrat from Uttar Pradesh, as he was a member of CCI but yielded after the agency decided to inform the Supreme Court about not getting the sanction to proceed against him.
During his period, 68 coal blocks were allotted to 151 companies and files of some of them had gone missing.
The government gave the permission on June 11 and a day later Gupta submitted his resignation from CCI.
CBI, which is probing the coal block allocation scam, has registered 13 FIRs related to alleged irregularities in the allotment coal blocks between 2006 and 2009.
In a recent FIR, CBI has named as accused Congress MP Naveen Jindal, former Minister of State for Coal D Narayana Rao and unknown officials of the Screening Committee which clears allocation of coal blocks and is normally chaired by coal secretary.
The agency questioned Gupta about the clearances for the allocation of coal blocks given by Screening Committee which was chaired by him on several occasions.
The CBI sources said the committee did not follow the mandatory procedures and did not carry out proper background checks while allocating coal blocks to the companies.
In its status report filed on March 8, the CBI had said that the coal blocks allocation during 2006-09 was done without verifying the credentials of companies which allegedly misrepresented facts about themselves and no rationale was given by the coal ministry in giving coal blocks to them.
Last month, CBI had received flak from the Supreme Court for sharing its status report in the coal scam with the then Law Minister Ashwani Kumar and senior officials of the PMO and the Coal ministry and also incorporating changes suggested by them.
The apex court had said that sharing of information with the government about the probe into the scam has "shaken the entire process" and asked CBI not to take instructions from "political masters" on their probe.
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