The S&P BSE Sensex and NSE Nifty 50 Indexes fell for a fourth straight day led by declines in bluechip stocks like Reliance Industries, Larsen & Toubro, Axis Bank, HDFC Bank, ICICI Bank and Tata Steel. In intraday deals today, the Sensex fell as much as 540 points to trade below 39,000 for first time in over three weeks while the Nifty 50 Index touched intraday low of 11,657.75. The benchmarks opened on a weak note as Asian shares wobbled near one-week lows on Monday as investors turned cautious ahead of a closely-watched Federal Reserve meeting, while political tensions in the Middle East and Hong Kong kept risk appetite in check.

The Sensex plunged 491 points or 1.25 per cent to settle at 38,960 and the NSE Nifty Index fell 1.3 per cent or 151 points to shut shop at 11,672.

All the 19 sector gauges compiled by BSE ended lower led by the S&P BSE Metal Index's 3 per cent decline. Oil & Gas, Energy, Telecom, Auto, Capital Goods, Consumer Durables and Bankex Indexes also dropped between 1.2 and 2.5 per cent each.

Mid- and small-cap shares also witnessed selling pressure as the S&P BSE MidCap and S&P BSE SmallCap Indexes fell 1.3 per cent each.

In the Nifty 50 basket of shares, 46 ended lower while only four shares ended higher.

Tata Steel was top loser in the Nifty, the stock fell 5.78 per cent to close at Rs 472.80. JSW Steel, Tata Motors, Indiabulls Housing Finance, ONGC, Vedanta, Indian Oil, Sun Pharma, Reliance Industries and Axis Bank also fell between 2.5 and 4 per cent each.

On the flipside, Yes Bank, Coal India, Wipro and Infosys were among the notable gainers.

The overall market breadth was extremely bearish as 1,879 shares ended lower while 685 closed higher on the BSE.