The Sensex opened with a negative gap of 170 points at 9,160, since then has extended losses and is now down 257 points at 9,072.
Bharti Airtel has slumped 5% to Rs 615. Reliance Communications, ICICI Bank and HDFC have plunged 4.7% each to Rs 176, Rs 394 and Rs 1,475, respectively.
Sterlite and Grasim have shed 3.7% each at Rs 260 and Rs 1,199, respectively.
Jaiprakash Associates, HDFC Bank, Maruti, SBI and Tata Steel have slipped around 3.5% each to Rs 67, Rs 907, Rs 558, Rs 1,107 and Rs 201, respectively.
ONGC, DLF, Hindalco and Reliance have declined over 3% each to Rs 649, Rs 189, Rs 49 and Rs 1,192, respectively.