Former TMC leader Sovan Chatterjee, who recently joined the BJP, was being questioned by CBI on Thursday in connection with the multi-crore Saradha scam, sources in the central agency said.
Mr Chatterjee, a former Mayor of Kolkata, was accompanied by his friend Baisakhi Banerjee to the CBI office at CGO Complex in Salt Lake.
He arrived there at around 12.30 pm.
Mr Chatterjee had earlier been questioned by sleuths of the investigating agency in connection with the scam.
The Supreme Court had ordered a probe into the scam and transferred the case to the CBI in 2014.
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