Mumbai: Stock markets opened on a weak note on Friday morning, with deepening worries of a global economic slowdown dragging the benchmark Sensex down by over 300 points in early trade.

The Bombay Stock Exchange Sensex fell by 351.37 points in opening trade to 16,118.42, while the National Stock Exchange's 50-share Nifty index slipped below the 4,900-point mark with a fall of over 100 points.

Heavy selling was witnessed in IT and banking stocks, with blue-chips like Infosys, ICICI Bank, TCS and HDFC Bank falling sharply.
Stocks like RIL and Tata Motors were also down.

Brokers said the sentiment on the domestic bourses remained distinctly bearish after Asian stock markets plummeted by nearly 4 percent following overnight losses in the US market on weak economic data for the American economy and renewed concerns about the eurozone debt crisis.

Earlier on Friday morning, the Sensex had plunged by over 200 points in pre-opening trade, while the Nifty was down by 85 points. The markets lost further ground after the market opened for normal trading.

The sharp overnight plunge of 4-6 percent in the benchmark indices in the US led to the heavy fall in other Asian markets too. Stocks in China were down over 1 percent, while markets in Japan, Hong Kong, Australia and Taiwan were down by over 2 percent.

European markets also fell sharply on Thursday amid deepening fears of major global economies, including the US, dipping into a recession again.

Indian stocks had plunged sharply yesterday as well amid global market turmoil, with the Sensex tanking by 371 points to 16,469.79, its lowest level in nearly 15 months.