New Delhi: The CBI has taken over the probe into the killing of BJP workers Pradeep Mondal, Devdas Mondal, and Sukanta Mondal during the 2019 post-poll violence in Sandeskhali and registered an FIR against prime accused and former TMC leader Sahajahan Sheikh, officials said.The agency registered the first information report (FIR) on the orders of the Calcutta High Court on June 30, the officials said on Saturday.Justice Joy Sengupta has ordered the Central Bureau of Investigation (CBI) to constitute a special investigation team (SIT) to probe the case with "utmost seriousness". The court said the investigation should be supervised by a joint director. Pradeep Mondal, Devdas Mondal and Sukanta Mondal were found dead after an alleged attack on their village in Sandeshkhali, allegedly by a mob led by Sheikh.The case was probed by the CID of the West Bengal Police. The families of the victims had later approached the Calcutta High Court seeking a CBI probe. Sheikh was arrested on January 5, 2024, in a case of alleged attack on Enforcement Directorate officers during a raid at his Sandeshkhali home. He has been in judicial custody since then."In the present case too, which has even more serious charges, I find that the police failed to take action against the prime accused at different stages, leading to gross miscarriage of justice. It would, thus, not be in the interest of justice to again give the reins of investigation to them," Justice Sengupta noted while handing over the probe to the CBI.He said it appears that whenever allegations are levelled against the said accused -- Sheikh-- the state police "tend to falter, be it in the above-referred case of mob violence against the ED Officials or in the instant case." "In this, no distinction can be made between the local police (as in the said earlier case) or the CID (as in the present case)," he said.Several women in Sandeshkhali in 24 North Parganas, a riverine island around 80 km from Kolkata had alleged land grabbing and sexual abuse by Sheikh and his men, who are involved in fish farming and trading. In January 2024, officers of the ED were allegedly assaulted and their vehicles were damaged when they went to the residence of Sheikh to conduct a raid in connection with the multi-crore ration distribution scam. The agency is already probing these three cases related to the attacks on the ED team.