The CBI on Monday searched the offices and residence of three officials of the Securities and Exchange Board of India (Sebi) in connection with the Saradha case, ratcheting up the probe ahead of the Assembly polls.

It is learnt that the top official targeted by the CBI is a chief general manager who headed operations of the market watchdog in Calcutta between 2009 and 2013. The other two are general managers who were also based in the city during that period.

There was no official comment from the market regulator on the searches.

The Saradha group of companies has been accused to duping lakhs of people of around Rs 2,500 crore by promising them high rates of returns on their deposits.

In April 2013, Rajeev Kumar Agarwal, Whole Time Member, SEBI had passed an order directing Saradha Realty India Ltd. and its managing director, Sudipta Sen, to wind up its collective investment schemes and refund the money collected under the schemes at the promised rates within a period of three months from the date of the order.

The company was also asked to submit a winding up and repayment report to the market regulator.