Equity indices plunged on Monday with the benchmark BSE sensex falling more than 1,700 points amid heavy sell-off across sectors as Covid-19 cases continued to surge in the country. The 30-share BSE index was trading 1,708 points or 3.44 per cent lower at 47,883; while, the broader NSE Nifty was down 524 points or 3.53 per cent at 14,311.