Sinking to its lowest level in over four months, benchmark Sensex on Friday crashed 699 points, its biggest single-day fall since February 11, to drop below the key 27,000-level on sustained foreign fund outflows combined with weakening trend globally. Besides, the rupee breaching the 67-mark against the US dollar by plunging 59 paise to 67.22 (intra-day) at the forex market too had its bearing.

Offloading of positions by cautious participants ahead of September IIP data, to be released later in the day, also added to weakened sentiment.

Investors seemed to be cautious on fears that US President-elect Donald Trump's planned huge spending policies would be inflationary which may lead to higher US interest rates and dent the appeal of emerging markets.

The Sensex after opening lower at 27,344.85 continued to slide on heavy selling pressure in blue-chips, forcing the index to touch a low of 26,777.18 before settling at 26,818.82, down 698.86 points, or 2.54 per cent, its biggest single-day fall since February 11 when it had lost 807.07. This was the weakest closing since June 29, 2016.

The gauge had rallied 265.15 points in the previous session. The 50-share NSE Nifty broke 8,300-mark after plunging 229.45 points, or 2.69 per cent, to 8,296.30, its lowest closing since June 30.

For the week, the Sensex dropped 455.33 points, or 1.66 per cent, while the Nifty lost 137.45 points, or 1.62 per cent. The fall was so widespread that 29 Sensex stocks closed with losses including M&M, Adani Ports, ICICI Bank, Tata Motors, Hero MotoCorp, Asian Paint, HDFC Ltd, Maruti Suzuki, GAIL, Bajaj Auto, Power Grid and TCS, falling up to 6.02 per cent. Only Sun Pharma ended in the green territory by recording a rise of 3.30 per cent on the back of better-than-expected quarterly earnings.