The Sensex opened flat at 13,570, and slipped into negative zone in morning deals tracking other Asian markets.Unabated selling in select index heavyweights like ONGC, HDFC, ICICI Bank and Reliance Communications saw the index plunge to a low of 13,337 - down 1.5% (233 points) from the day's open.The Sensex finally closed wih a loss of 204 points at 13,362. The index has now shed 4.7% (653 points) in five straigth sessions from its all-time closing high of 14,015 registered on January 3.Infosys Q3 numbers, which will be announced tomorrow, are likely to determine the trend for the coming days.The Bankex and PSU index plunged 2.5% each to 6845 and 5929, respectively. The Healthcare index shed 1.4% to 3738. The Metal and TECk indices slipped over 1% each to 8678 and 3519, respectively. The BSE Mid-cap and Small-cap indices were also down around 1% each at 5819 and 7146, respectively. Declines beat advances nearly 2:1 - out of 2,707 stocks traded, 1,712 declined, and 952 advanced today.INDEX MOVERS & SHAKERSBHEL tumbled nearly 5% (Rs 105) to Rs 2,144. Reliance Communications slumped nearly 4% to Rs 407.ICICI Bank, SBI, ONGC and Dr.Reddy's dropped around 3% each to Rs 883, Rs 1,137, Rs 890 and Rs 775, respectively.HDFC & Reliance Energy slipped over 2% each to Rs 1,527 and Rs 505, respectively.NTPC, Gujarat Ambuja, Bharti Airtel and TCS shed around 2% each to Rs 133, Rs 137, Rs 613 and Rs 1,234, respectively.Wipro, however, surged nearly 2% to Rs 591.VALUE & VOLUME TOPPERSDebutant Shree Ashtavinayak topped the value chart with a turnover of Rs 364 crore followed by Pyramid Saimira (Rs 140 crore), Reliance Communications (Rs 130 crore), Tech Mahindra (Rs 118.50 crore) and Reliance (Rs 113 crore).IFCI led the volume chart with trades of around 4.70 crore shares followed by Shree Ashtavinayak (1.60 crore), Pentium Infotech (1.59 crore), Zee News (1.37 crore) and Vishal Exports (83 lakh).