CBI sources said the 81-year-old Chief Minister appeared for questioning at the agency headquarters in New Delhi.
The agency had initiated an inquiry which had allegedly showed that as Union minister during 2009-2012 under United Progressive Alliance rule, Singh had allegedly accumulated assets worth Rs 6.03 crore (approx) in his name and in the name of his family members which were found to be disproportionate to his known sources of income, the CBI has said.
A first information report filed with a designated court in Delhi under the prevention of corruption act, named Singh, his wife Pratibha Singh, LIC agent Anand Chauhan and Chunni Lal Chauhan.
The allegations have been refuted by Singh.
In a statement, the CBI spokesperson had said it was further alleged that Singh had invested his unaccounted income in LIC policies in his name and in the name of his wife and other family members through a private person by showing the same as agricultural income.
"This was done by creation of a MoU purportedly dated June 15, 2008 for maintenance of an apple orchard, with the said private person (Chauhan) for a period of three years. The private person had allegedly deposited Rs five crore cash (approx) in his own bank account and debited the same through cheques for purchasing various LIC policies in their names," the CBI had said.
It had said Singh allegedly attempted to legitimize the same as agricultural income by filing revised income Tax returns in 2012.
"The agricultural income as claimed by him in his revised ITRs was not found to be tenable. The then Union minister had allegedly accumulated other assets disproportionate to known sources of income," the CBI has alleged.
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