Mumbai, Aug 13 - Indian equities markets opened on a positive note Thursday, with a key index gaining 1.76 percent within 20 minutes of start of trade.

The sensitive index (Sensex) of the Bombay Stock Exchange (BSE) opened at 15,207.96 points, as against Wednesday's close at 15,020.16 points. It soon rose to 15,283.92 points, 263.76 or 1.76 percent up from its previous close.

The S&P CNX Nifty of the National Stock Exchange (NSE) too was trading in the green at 4,534.2 points, a rise of 1.72 percent.

Broader market indices were also in the positive terrain with the BSE midcap index up 2 percent, while the BSE smallcap index was 2.43 percent higher.