New Delhi: The Central Bureau of Investigation (CBI) has sought prosecution sanction for three TMC MPs and one former MP of the party from Lok Sabha Speaker, Om Birla, in connection with the Narada sting operation case, sources in the know here said on Thursday.The central probe agency has sought sanction to prosecute Prasun Banerjee, Kakoli Ghosh Dastidar and Saugata Roy – all sitting members of the 17th Lok Sabha – and former TMC MP Suvendu Adhikary. Interestingly, no prosecution sanction has been sought for Mukul Roy, who jumped ship to the ruling BJP, within four months of CBI registering its FIR. Also Read – Uddhav bats for ‘Sena CM’While the sanction to prosecute these four accused in the Narada case was sought almost nearly four months ago from the former Speaker of the Lower House, the probe agency has sent a reminder to Birla with regards to the sanction. All four of these senior Trinamool Congress members have been questioned by the CBI in the Narada case, which came up after video footage was released, purportedly showing several senior members of the ruling party in West Bengal demanding and accepting cash bribes. Also Read – Farooq demands unconditional release of all detainees in J&KThe series of videos, dubbed the Narada tapes, was first released on Narada News, owned and operated by Matthew Samuel, who had visited senior party leaders pretending to be the owner of a fictitious company, asking for favours. The CBI’s preliminary probe in the case had established that Dastidar, Adhikary and Roy were all seen accepting Rs 5 lakh in cash from Samuel, who was the sting operator, covertly recording his meetings with the leaders. In the Narada tapes, the probe agency has also established that Banerjee was shown accepting Rs 4 lakh in cash. However, all four have consistently denied that the money they were shown accepting was bribe amount, insisting to the probe agency that Samuel had pretended to donate to their election campaign before the 2014 Lok Sabha polls. Meanwhile, the central probe agency has also summoned 11 people accused in the Narada case to appear before agency officials in Kolkata, so their voice samples can be collected, as mandated by the Supreme Court of India. This list of 11 includes ex-TMC MLA Sovan Chatterjee, TMC MP Aparupa Poddar, former TMC MP Sultan Ahmed and other politicians accused in the case, except senior BJP leader Mukul Roy, formerly of the Trinamool Congress. Even though the CBI has established that Mukul Roy had demanded money and indicated that an IPS officer, SMH Meerza would accept it on his behalf, the probe agency has not sought sanction to prosecute him as of yet. In fact, the tapes also show Meerza accepting cash amounts on behalf of Mukul Roy. The role of investigators in the case, is as a result, being perceived to be very controversial.