Indian markets dropped sharply on opening Friday with the 30-share benchmark Sensex of the Bombay Stock Exchange dipping by about 3.3 per cent to below the 16,000-point mark, DPA reported. The broader 50-share Nifty of the National Stock Exchange fell to 2472.10 points at noon, about 4.93 per cent below its close of 2600.20 points on Wednesday. Indian equity markets were closed Thursday on occasion of a national holiday. The sharp fall tracked Asian markets which showed a downward trend amid growing concern over credit problems in the United States. Major energy stocks like Reliance Energy, Tata Power and Suzlon Energy were among the top losers. But losses were seen across the board and included information technology and telecom firms like Infosys, Satyam Computers and Reliance Communications as well as ICICI Bank, real estate developer DLF and Seimens India.