The Indian benchmark indices, Sensex and Nifty, opened on a strong note, extending gains as both traded in positive territory. The Sensex is steadily trending upwards, up over 1,000 points while the Nifty is trading around the 23,600 mark. The S&P BSE Senses added 1,003.06 points to 77,908.57, while NSE Nifty50 gained 286.95 points to 23,637.35 as of 12:37 pm.