"The state and central governments might have an unholy nexus, as a result of which Madan Mitra got bail," state Congress president Adhir Chowdhury said at Bhatar in Burdwan district.
CBI failed to furnish specific proof against Mitra, claimed Chowdhury, an MP and former union minister.
Mitra was granted conditional bail by ACJM (in-charge) of Alipore District and Sessions Court Partha Das 10 months after his arrest. CBI said it would move a higher court.
The district administration, however, said the deaths had no relation with crop failure but was due to ill health and family problems.