NEW YORK (MarketWatch) -- As U.S. stocks saw their biggest sell-off in two months, Alcoa and Bank of America dragged Monday on the Dow Jones Industrial Average, while a poorer-than-expected earnings performance felled Walgreen.

The Dow industrials dropped 200.72 points, or 2.4%, to 8339.01, now having fallen five of the last six sessions, for a drop of 460.25 points, or 5.2%. The Standard & Poor's 500-stock index fell 28.19 points, or 3.1%, to 893.04. The Nasdaq Composite Index dropped 61.28 points, or 3.4%, to 1766.19. All three indices suffered their biggest point and percentage drops since April 20.