The wider 50-scrip Nifty of the National Stock Exchange (NSE) also was trading 47.05 points or 0.59 percent down at 7,884.30 points.
The Sensex of the S&P Bombay Stock Exchange (BSE), which opened at 26,123.86 points, was trading at 25,957.91 points (at 12.44 p.m.) in the afternoon session, down 159.94 points or 0.61 percent from the previous day's close at 26,117.85 points.
The Sensex has touched a high of 26,123.86 points and a low of 25,952.17 points in the trade so far.
Good buying was observed in telecom sector, while selling pressure was seen in fast moving consumer goods (FMCG), healthcare and auto sectors.
The telecom index gained by 0.49 percent, while the FMCG index fell by 1.29 percent, healthcare index dropped by 0.71 percent and auto index went down by 0.67 percent.(IANS)