Indian markets logged their worst single-session drop in eight weeks today with Sensex plunging about 339 points and Nifty slipping 100 points on losses in Infosys, where co-founders sold USD 1 billion worth shares, and other bluechips like TCS, HDFC Bank and ICICI Bank. M&M, Sesa Sterlite, Dr Reddys, Hindalco and Tata Steel counters dropped in 2-4 per cent range. L&T, RIL and Tata Motors were also under pressure. The 30-share BSE Sensex fell to touch the day's low of 28,097.12 following fall in recent outperformers like HDFC Bank and ICICI Bank. However, the index attempted to rebound as it touched the session's high of 28,494.85 on value buying. Participants, however, later again resorted to selling, spread over a broad front. Sensex settled the day at 28119.40, down 338.70 points, or 1.19 per cent. On Friday, it had slipped 104.72 points on profit-selling. This 338.7-point drop is its worst since October 16 when it fell 349.99 points. On similar lines, the NSE 50-share Nifty dipped below the key 8,500-mark by tumbling 100.05 points, or 1.17 per cent, to close, at 8,438.25. Intra-day, it traded in a range between 8,432.25 and 8,546.35. This was also its worst drop since October 16 (fall of 115.80 points). "The decline was led by the IT counters as sentiments got a hit after some of the founders of IT major Infosys decided to sell USD 1.1 billion shares. Further, profit booking in capital goods, consumer durables and banking stocks also pushed the benchmark in red," said Jayant Manglik, President-retail distribution, Religare Securities. Infosys counter fell 4.88 per cent, the worst performer in Sense,. TCS tumbled 2.51 per cent and Wipro shed 1.62 per cent in line with weak trend in IT shares. Shares of metal companies, including Sesa, Hindalco and Tata Steel, faced selling after weak Chinese trade data. Sectorwise, BSE IT index suffered the most by losing 3.18 per cent, followed by Teck 2.58 per cent, Realty 1.80 per cent, Capital Goods 1.72 per cent and Consumer Durables 1.41 per cent. Overall, 11 of the 12 sectoral indices ended in red. Pressure was also seen in smaller stocks. BSE Small cap index ended 0.87 per cent down while the Mid-cap index shed as much as 1.22 per cent. Global cues were mixed with Asian bourses ending higher and Europe was down in its opening trades. Foreign Portfolio Investors sold shares worth net Rs 109.45 crore on Friday as per provisional data.