A benchmark index of Indian equities markets, the 30-scrip Sensitive Index (Sensex), on Tuesday was trading 67.31 points or 0.23 percent down in the early session as auto stocks tanked.The wider 50-scrip Nifty of the National Stock Exchange (NSE) was also trading 15.25 points or 0.17 percent down at 8,941.50 points.The Sensex of the S&P Bombay Stock Exchange (BSE), which opened at 29,500.19 points, was trading at 29,391.83 points (at 9.23 a.m.) in the early session, down 67.31 points or 0.23 percent from the previous day's close at 29,459.14 points.The Sensex touched a high of 29,502.62 points and a low of 29,364.87 points in the trade so far.Heavy selling pressure was seen in auto, metal and banking stocks. Good buying was observed in the health care sector.