Equity indices Sensex and Nifty fell over 1% on Tuesday, driven by weak global trends, foreign fund outflows, and a sell-off in auto and banking stocks. The BSE Sensex lost 821 points, closing at 78,675, while the Nifty shed 258 points to settle at 23,883. Almost all sector indices ended in the red, with foreign institutional investors offloading equities worth over 2,306 crore rupees.