The Sensex is trending lower on the back of heavy selling pressure in index heavyweights. The Sensex is now down 662 points at 10,147.
The NSE Nifty is down 203 points at 3,135.
Mahindra & Mahindra and Reliance have slumped 9.7% each to Rs 437 and Rs 1,372, respectively.
Wipro, TCS and Jaiprakash Associates have crashed around 9% each to Rs 252, Rs 494 and Rs 66, respectively.
Tata Motors has tumbled 8.7% to Rs 258. Hindalco, Infosys and Sterlite have plunged around 8% each to Rs 73, Rs 1,225 and Rs 269, respectively.
Grasim has dropped over 7% to Rs 1,383. Tata Power has shed 6.5% at Rs 743.
BHEL, Bharti Airtel and HDFC Bank have slipped nearly 6% each to Rs 1,313, Rs 677 and Rs 1,069, respectively.
ACC, Larsen & Toubro and Satyam are down around 5.5% each at Rs 514, Rs 843 and Rs 257, respectively.
Hindustan Unilever, however, has surged 2.5% to Rs 237.
Earlier Report
The Sensex opened with a negative gap of 524 points at 10,285, and soon tanked to a fresh calendar year low of 10,151.
The index is now down 450 points at 10,360. The NSE Nifty is down 139 points at 3199.
Reliance and TCS have slumped over 8.5% each to Rs 1,386 and Rs 496, respectively.
Jaiprakash Associates and Sterlite have plunged 8% each to Rs 67 and Rs 269, respectively.