"This is as an illegal move to break CPI(M). This sort of a thing has not happened during the Emergency period," Vijayan, now on his 'Kerala raksha march', told reporters.
In another development, a fresh case was registered at Edachery police station in Kozhikode district on Tuesday, based on a complaint by Rema, alleging that her husband was the victim of a political conspiracy.
He also accused a section of media of supporting this move, instead of looking at things in an objective and impartial manner.
A CPI(M) rebel who floated a parallel Left outfit called Revolutionary Marxist Party in his home turf Onchiayam in north Kerala, Chandrasekharan was hacked to death in May 2012.
The state Government is under pressure to recommend a CBI probe to unearth the 'conspiracy' behind the murder with the RMP leader's wife K K Rema on an indefinite fast since Monday in front of the secretariat here, demanding such an inquiry.
Many Congress leaders in the state have come out and pledged solidarity with Rema, who also received support from the BJP and several human rights campaigners.