The Indian equity benchmarks ended sharply lower for second straight session on Wednesday and suffered their biggest single-day loss in January on the back of weak global cues as investor sentiment took a knock globally after a drone attack on UAE's Adnoc pushed crude prices higher and equity markets down across the world, analysts said. The benchmarks staged a gap down opening and extended losses wherein the Sensex fell as much as 805 points and Nifty 50 index briefly dropped below its important psychological level of 17,900.