The Sensex is now down 408 points at 10,276.
Reliance Communications, Bharti Airtel and Tata Steel have slumped over 7.5% each to Rs 238, Rs 669 and Rs 257, respectively.
TCS, Sterlite and Mahindra & Mahindra have plunged 6% each to Rs 527, Rs 277 and Rs 384, respectively.
ICICI Bank, Tata Motors and Hindalco have dropped around 5.5% each at Rs 407, Rs 234 and Rs 61, respectively.
Grasim and Reliance have shed 5% each at Rs 1,148 and Rs 1,328, respectively.
ITC, however, has gained nearly 3% at Rs 174.
The market breadth is fairly negative - out of 2,341 stocks traded so far, 1,542 have declined, 721 have advanced and the rest are unchanged.