The Bombay Stock Exchange benchmark Sensex lost 447 points in early trade on Friday on heavy selling by funds, tracking weak global markets.
The 30-share index, which lost 165.27 points in Thursday's trading, tumbled by 446.84 points to 14,330.17.
Similarly, the wide-based National Stock Exchange's index Nifty moved down by 124 points to 4,309.55 as heavy-weight stocks such as Reliance Industries, Infosys Technology, Acc, and ITC Ltd suffered heavy losses.
Marketmen said selling pressure developed after global markets, including Hong Kong and Singapore fell sharply in early trade.
They said Hong Kong share prices opened down 1.5 per cent tracking declines in regional bourses following a fall on Wall Street.
The Wall Street tumble was triggered by a steeper-than-expected 2.6 per cent drop in the US home sales figures in June, and worries about the financial sector amid mixed second-quarter corporate earnings results.