The former coal secretary recently came out with a book in which he questioned the CBI's decision to register a case against him and said if he was guilty then the prime minister should also have been named in the FIR.
Official sources said that some of the top executives of Rs 2.4 lakh crore Birla company were called in connection with the allocation of the coal block in Odhisa.
While there was no decision immediately to summon the group's chairman Kumarmanglam Birla, the sources said that 68-year-old Parakh is likely to be questioned next week.
CBI had registered a case naming 46-year-old Birla, Parakh and unknown officials of Hindalco and coal ministry last year under various sections pertaining to criminal conspiracy and corruption for alleged irregularities in the allocation of coal blocks nine years back.
The decision to call executives of the Birla group was taken after a senior PMO TKA Nair was examined about the entire coal scam especially on Talabira-II.
Nair, who had replied to a CBI questionnaire, had denied any wrong doing in allocation of coal blocks to Hindalco. Registering of a case against Birla and Parakh was criticised by India Inc and former bureaucrats.
The sources said that after completing the investigations in the case, CBI would take a decision whether the agency should file a charge sheet or move a closure report in the court.
Hindalco has been denying allegations of irregularities. "We wish to state unambiguously that we have followed every process required for allocation of coal completely, as stipulated by the Government policy."
"This relates to media reports on an FIR naming Hindalco and our chairman on coal issues. Apparently, this seems to be part of a larger case entailing coal allocation to companies, and being one of the companies, we are being investigated also," it had said.
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