The Bombay Stock Exchange benchmark Sensex on Wednesday suffered the most this year by losing 749 points on panic selling by funds after Satyam Computer said profit had been inflated for years, raising concerns of dim third-quarter earnings by blue-chip companies.

The Sensex, which had gained over 688 points in the last four sessions of 2009, tumbled below the crucial 10,000 point level, losing 749.05 points to reach 9,586.88. It touched the day's low of 9,510.15 and a high of 10,469.72 points, showing a wide fluctuation of nearly 960 points.

Satyam Computer crashed by Rs 139.15 or 77.69 per cent to close at Rs 39.95, after the Chairman announced the company had falsified accounts and assets for several years.

Amazingly, the company ADR on the US stock market -- Nasdaq -- closed higher by four per cent last night.

The declining Sensex recorded the biggest single-day loss in the past two months, after Satyam Computers Services, the country's fourth-largest software developer, plunged around 80 per cent, the highest since getting listed in 1992.

The 50-share National Stock Exchange index Nifty tumbled by 192.40 points at 2,920.40, after hitting the day's low of 2,888.20 points during the day.

Reliance Industries, with the highest weight in the Sensex, fell 12.52 per cent to Rs 1,196.80, the most since November 5. ICICI Bank, the second-largest lender, fell 10.53 per cent to Rs 468.05, the most since October 24.

With the market sentiment shattered, five of the 30 Sensex stocks were higher on selective buying. They were Infosys Technologies, Maruti Suzuki, Wipro, Grasim and Hindustan Unilever.