Alert: Stocks fall sharply as worries mount about weakening US economy. Dow drops 600, Nasdaq closes 10% below July high (CORRECTS: A previous APNewsAlert erroneously reported the Nasdaq's most recent high occurred in June})

Stocks fall sharply as worries mount about weakening US economy. Dow drops 600, Nasdaq closes 10% below July high (CORRECTS: A previous APNewsAlert erroneously reported the Nasdaq's most recent high occurred in June}).