The 30-share index, which opened in positive zone, fell by 350.32 points, or 1.82 per cent to trade at 18,942.88 at 1130 hrs after RBI left cash reserve ration (CRR) unchanged at 4 per cent and announced a cut in short-term lending, repo, rate by 0.25 per cent to 7.5 per cent.
All the sectoral indices, led by oil and gas and banking, were trading in negative, with losses of up to 2.47 per cent.
On similar lines, the National Stock Exchange Nifty index Nifty fell bellow 5,800 level by declining 100.65 points, or 1.72 per cent, to 5,734.60 points.
Brokers said a cut in short-term lending rate by 0.25 per cent to 7.75 per cent after a gap of nine months, and reducing Cash Reserve Ratio (CRR) by 0.25 per cent to 4 per cent by the Reserve Bank brought cheer to the market as the move would reduce the cost of home, auto and corporate loans and improve liquidity in the market.
They said a cut in CRR would have benefited banks by easing liquidity.
The BSE banking index fell by 1.97 per cent to 13,209.95 as stocks of state-run State Bank of India fell 1.98 per cent to Rs 2,204, ICICI Bank by 1.36 per cent to Rs 1,036.85, HDFC Bank by 2.09 per cent to Rs 630.10 and Axis Bank by 1.78 per cent to Rs 1,301.25.