The Indian equity benchmarks on Monday extended fall to the fifth straight session amid an across-the-board sell-off. The 30-share BSE Sensex crashed 1,546 points or 2.62 per cent to close at 57,492, while the broader NSE Nifty settled 468 points or 2.66 per cent lower at 17,149. During the day, the 30-share BSE index hit an intraday low of 56,984; and Nifty touched a low of 16,998. Sensex has plunged more than 3,800 points in the last five trading sessions. Both the domestic indexes have tumbled nearly 6 per cent, respectively.