Unabated selling in the banking, metal and capital goods stocks saw the index tumble to a low of 16,300 - down 349 points from its previous close.
The Sensex finally ended (provisional) with a loss of 246 points at 16,403.
The market breadth was negative - out of 2,758 stocks traded, 670 advanced, 2037 declined and 51 were unchanged today.
The NSE Nifty settled (provisional) with a loss of 71 points at 4,875.