"This has been accompanied by vicious and illegal bear hammering of our listed stocks, to create panic and destabilise the markets," a group spokesperson said in an emailed statement.

It said it had asked the Securities and Exchange Board of India and the stock exchanges to investigate.

Shares in group listed companies Reliance Power, Reliance Communications, Reliance Capital, and Reliance Infrastructure ended between 8.9 and 18.8 percent lower after a sharp selloff in the last 90 minutes of trade.The BSE Sensex ended about 1 percent lower.