Lucknow: In order to tighten the noose around the alleged ministers and bureaucrats for siphoning off National Rural Health Mission funds, the Central Bureau of Investigation (CBI) is keeping a close tab on the call details of firms, contractors and prominent figures of the ruling BSP government who are under suspicion.

According to sources, CBI is keeping close watch those ministers who have either resigned or were sacked from the Mayawati government. It includes former Family Welfare Minister Babu Singh Kushwaha, Health Minister Anant Kumar Mishra and officials, MPs, legislators close to them.

To probe into the NRHM scam, sleuths have taken out call details of contractors and suspected officials. Contractors who were given funds for the construction of health care centres in Jaunpur, Poorvanchal and other districts are quizzed by CBI. To collect the evidence, the investigating agency is also studying the details of the expenditure made through NRHM fund.