Sustained selling in noon deals saw the index slip below the 8,000-mark, and drop to a low of 7,923 - a drop of 199 points from the last close of 8,122.
The Sensex finally closed with a loss of 151 points (1.9%) at 7,971.
The Nifty lost 56 points to close at 2,412.
ONGC dropped 3.6% (Rs 35) to Rs 947. While Reliance lost 1.3% (Rs 10) to Rs 748, SBI declined Rs 22 (2.5%) to Rs 889.
HLL slipped over 3% (Rs 6) to Rs 169, and ITC was also down over 3% (Rs 4) at Rs 121.
TCS declined 2.5% (Rs 36) to Rs 1,402. Infosys lost Rs 31 to Rs 2,500.
Dr. Reddy's tanked 4.4% (Rs 38) to Rs 817. Cipla slipped 3.5% (Rs 14) to Rs 382. Ranbaxy was down 1.9% (Rs 8) at Rs 411.
Hero Honda declined over 4% (Rs 29) to Rs 688. Bajaj dropped Rs 43 to Rs 1,731. Maruti and Tata Motors declined over 2% each today.
L&T dropped 3.6% (Rs 52) to Rs 1,381. Grasim was down Rs 23 at Rs 1,148. BHEL declined Rs 14 to Rs 1,158. Tata Steel, Bharti and Hindalco closed with losses of over 3% each today.
Satyam was up Rs 5 at Rs 557. ACC and ICICI Bank also finished with gains.