Mumbai, April 17 -- The key equity indices traded with significant gains in early afternoon trade, as investors awaited the Q4 results of ICICI Bank and HDFC Bank, which are scheduled to be announced later this week. The Nifty traded near the 23,650 mark. Private bank shares surged for the fourth consecutive trading session.

At 12:25 IST, the barometer index, the S&P BSE Sensex, advanced 767.50 points or 1% to 77,824.58. The Nifty 50 index added 208.75 points or 0.89% to 23,645.95.

In the broader market, the S&P BSE Mid-Cap index advanced 0.30% and the S&P BSE Small-Cap index rose 0.61%.

The market breadth was strong. On the BSE, 2,447 shares rose and 1,304 shares fell. A total of 193 shares were unchanged.

Derivatives :

The NSE's In...