Judge Anil Kumar Mishra also slapped a fine of Rs 10 lakh on Mr Bhuyan. If he fails to pay the fine amount, Mr Bhuyan will have to spend one more year in jail.
According to CBI sources, the complaint against Mr Bhuyan was lodged in 2013, following a Jharkhand High Court directive for an investigation by the central probe agency.
The probe revealed that Mr Bhuyan possessed assets worth Rs 1.03 crore, an amount disproportionate to his known sources of income, and the chargesheet was filed in 2014.
A three-time Jharkhand Mukti Morcha (JMM) MLA from Jugsalai Assembly constituency, Bhuyan was the land and revenue minister in the Shibu Soren and Madhu Koda governments between 2005 and 2009.
He had left the JMM ahead of the 2014 state Assembly polls and joined the Jharkhand Vikas Morcha, then the BJP, before joining the Congress.
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