Stock markets around the world have fallen sharply following warnings about economic outlook from the United States Federal Reserve. By early afternoon share prices in London and Paris dropped by about 5 per cent. Asia markets also closed substantially lower.Falling in tandem with tumbling global markets, the Sensex at the Bombay Stock Exchange posted its biggest single-day loss in over 26 months, plunging 704 points, or 4.1 percent, to 16,361, on Thursday. The Sensex had lost 232 points at the day's high and fallen 749 points at the day's low. The Nifty at the National Stock Exchange plummeted 210 points, or 4.1 percent, to 4,924. In the broader market, the BSE Midcap and Smallcap indices slid 3.1 percent, each.Market breadth was extremely weak on the BSE, with about 4 losers for every single gainer. The BSE clocked a turnover of 2,805 crore rupees on its cash segment.All the BSE sectoral indices ended in the red. The Realty index was the leading loser, sinking 5.7%. The Metal index plummeted 4.3%; the Oil and Gas and the Teck indexes plunged 4.1%, each; the Bankex, and the Auto, the IT, the Capital Goods and the Power indices tumbled about 3.8%, each; the Consuner Durables index slid 3.4%; the FMCG and the PSU indices declined about 2.6%, each; and the Healthcare index slid 2.2%.Index heavyweight Reliance Industries tumbled 6.5%. Offshore oil services providers declined as crude oil prices fell. Aban Offshore, Great Offshore, SEAMEC, Jindal Drilling and Dolphin Offshore shed between 0.2% and 8%. Larsen & Toubro fell 4.9%, although the company on Thursday said it has bagged a 700-crore rupee order in Oman.In banking majors, ICICI Bank plunged 5%. SBI declined 4% on likely weak Q2 results as the bank's advance tax payment declined 14%.Punjab National Bank, Bank of India and Bank of Baroda dropped between 3% and 4.5%. HDFC Bank fell 3.6% and Axis Bank shed 3.7%.Realty stocks slumped. DLF, HDIL, Indiabulls Real Estate and Unitech shed between 5.5% and 8.8%. Metal stocks also sank. Sterlite, SAIL, Nalco, Jindal Steel & Power, Tata Steel, JSW Steel, Hindustan Zinc, and Hindalco dropped by between 3.8% and 7.5%.Auto stocks extended recent losses. Mahindra & Mahindra, Ashok Leyland, Tata Motors, Hero MotoCorp and Bajaj Auto fell between 1.5% and 5.5%. Maruti Suzuki India declined 3.8%.