The Sensex had rebounded into the positive zone to a high of 15,998, but soon slipped back into red and is now down 79 points at 15,896.The NSE Nifty is up 15 points at 4,787.Larsen & Toubro has slumped 8.7% to Rs 2,729, and BHEL has tumbled over 5% to Rs 1,919.Maruti and Reliance Energy have plunged nearly 3% each to Rs 907 and Rs 1,235, respectively. HDFC has shed 2.5% at Rs 2,563.Bharti Airtel has zoomed 5% to Rs 789, and ACC has soared 4.5% to Rs 768.DLF and Bajaj Auto have surged nearly 4% each to Rs 684 and Rs 1,960, respectively.SBI, Tata Steel, HDFC Bank and Cipla have rallied 4% each to Rs 1,900, Rs 797, Rs 1,325 and Rs 206, respectively.Reliance Communications has moved up 2.5% to Rs 557, and ONGC has added 1.5% to Rs 557.Out of 2,686 stocks traded so far, 1,931 have declined, 708 have advanced and 47 are unchanged.