A fresh round of heavy selling has forced the Sensex slip to lower levels. The index is now down 122 points at 12,313.Cement stocks have cracked further. Gujarat Ambuja has slumped 6.7% to Rs 107. ACC has plunged 5.4% to Rs 914, and Grasim has shed 2.8% to Rs 2,240.Reliance has plunged 3.5% to Rs 1,070. ONGC has dropped 2% to Rs 1,429.ICICI Bank has declined 2.7% to Rs 642, and SBI is down 1.5% at Rs 961.Larsen & Toubro has gained nearly 4% at Rs 2,883.