Ruchi Soya Industries (down 26.70%), K S Oils (down 14.82%) and Karuturi Global (down 10%), slumped.

A report on the Indian stock markets prepared by the Intelligence Bureau (IB) suspects that a market operator Vimal Rathod was accumulating shares of these three firms on behalf of investor C Shivasankaran based on insider information. The IB has reportedly passed on the information to the Cental Bureau of Investigation (CBI) and the market regulator, the Securities and Exchange Board of India (Sebi) for further action.

The report said Rathod in conjunction with the promoters would buy the shares of Ruchi Soya from the open market via manipulative means and then organise a fall in the share price. Rathod would then pick up a sizeable chunk of the shares from the market in the names of various front companies. The idea was to take the price to Rs 500 levels and then dispose off 26% stake to a strategic investor.

The report further said Rathod was active in the K S Oils counter where he accumulated shares not only for himself but also on behalf of Sivasankaran.