The Sensex is now down 414 points at 12,641.
Sterlite has slumped 8% to Rs 395, and Tata Steel has plunged 7.7% to Rs 405.
Reliance has tumbled 6.4% to Rs 1,786, and ICICI Bank has shed 6% at Rs 518.
Bharti Airtel has dropped 5.5% to Rs 746. Tata Power, Tata Motors and TCS have slipped around 4% each to Rs 907, Rs 326 and Rs 645, respectively.
Infosys, Larsen & Toubro and Reliance Communications have declined 3.7% each to Rs 1,401, Rs 1,171 and Rs 331, respectively.
Reliance Infrastructure is down 3.3% at Rs 756, and Satyam is down 3% at Rs 309.
Ranbaxy has soared nearly 7% to Rs 269. Mahindra & Mahindra has moved up 1.4% to Rs 514, and Hindustan Unilever has added 1% to Rs 254.
Out of 2,444 stocks traded so far, 1,703 have declined, 684 have advanced and the rest are unchanged.