The Sensex has extended gains and is now up 528 points at 18,771.The NSE Nifty has gained 176 points at 5,493.ONGC and Reliance Communications (RCom) have soared over 6% each to Rs 1,113 and Rs 650, respectively.DLF and Wipro have surged 4.5% each to Rs 850 and Rs 457, respectively.SBI has rallied nearly 4% to Rs 2,270. BHEL, Reliance and Tata Motors have gained around 3.5% each at Rs 2,140, Rs 2,634 and Rs 780, respectively.TCS, NTPC and Tata Steel have moved up 3.3% each to Rs 960, Rs 212 and Rs 802, respectively.Satyam, Ambuja Cements and Infosys have advanced around 3% each to Rs 434, Rs 122 and Rs 1,638, respectively.Mahindra & Mahindra and ICICI Bank have also added 3% each to Rs 694 and Rs 1,232, respectively.Reliance Energy and Grasim are up 2.8% each at Rs 2,072 and Rs 3,090, respectively.Bharti Airtel, Cipla and ITC are up around 2.5% each at Rs 931, Rs 201 and Rs 210, respectively.