Calcutta, Aug. 16 : Calcutta, Aug. 16: The Bengal CPM leadership today moved to insulate its scandal-prone North 24-Parganas unit against the aftershocks of the murder of Sailen Das apparently over a soured land deal. As the unit's main rival factions went for each other's jugular, the high command embarked on a damage-control exercise to delink party leaders from a realtor-criminal nexus. Alarmed at the public outcry over the Dum Dum municipality chairman's murder, CPM state secretary Anil Biswas and Left Front chairman Biman Bose shut out the media. But, earlier in the day, they asked district bosses to ensure that tainted leaders did not influence or impede police investigations. "They have been asked not to protect any rogue realtors who may be wanted by the police. No matter how high a functionary is placed, we will not shy away from punishing him if he is found guilty of shielding a criminal," district secretariat member Amitava Nandi said. Senior CPM officials said the leadership was worried over reports saying that the "unholy and profit-making" alliance between a district secretariat member and some Dum Dum-based realtors and materials suppliers needed to be probed. "I have no views to offer today," Biswas said. But it is believed he and other top guns got the district leadership to rein in the member. By having the member "quarantined", the leadership hopes to provide sleuths the room to go for tainted leaders, small-time rogue realtors and criminals operating from R.N. Guha Road. Soon after Das' murder, the leaders and realtors vanished, forcing the police to mount a vigil in Dum Dum. Detectives are keeping touch with the local unit as important CPM leaders have been seen visiting the R.N. Guha Road offices in the past few years. An official said these visits had turned the realtors' establishments into local CPM offices. "These promoters and suppliers used to force people to purchase materials. Some of our important leaders looked very close to them as they spent a lot of time in their establishments," said another. The nexus between local CPM leaders and the realtors was allegedly brought to the notice of the district leadership by some zonal leaders, but they chose to shut their eyes to it. But Nandi denied this. "It is not true that we had reports about the activities of certain comrades," he said. The group is believed to have forced Das to clear the construction of a plaza in Dum Dum bypassing objections from the building department. They also tried to push him into clearing the licence for a plastic factory on Mall Road and attempted to grab the job for construction of a market complex with help from local CPM leaders.