The Indian equity benchmarks fell for third straight session on Wednesday dragged by losses in HDFC, HDFC Bank, Tata Consultancy Services, Kotak Mahindra Bank, Reliance Industries and Asian Paints. The benchmarks staged a gap up opening but gave up intraday gains owing to volatility due to weekly expiry of index futures and option contracts. The Sensex fell as much as 713 points from the day's highest level and Nifty 50 index touched an intraday low of 17,457 after hitting an intraday high of 17,663.