The Ramchandi coal block investigation is said to have examined former Prime Minister Manmohan Singh last year.
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The Ramchandi block lies next to another coal block — Utkal B-1 — owned by Jindal Steel, said the source.
Though the decision to close the preliminary enquiry was taken in December, the Chief Vigilance Commissioner’s office was informed only this month.
Meanwhile, the debt-laden JSPL continues to remain in talks with lenders to get its loan rescheduled. The company carries a consolidated net debt of Rs 45,500 crore of which Rs 28,000 crore is on the books of its steel business.