The Sensex has so far touched a high of 29,584.34 points and a low of 29,265.32 points during the intra-day trade. It fell by 42.25 points or 0.46 per cent, to 9,094.15 points.
The broader Nifty closed down 0.19 percent at 9,119.40, losing 0.34 percent for the week.
The barometer 30-scrip sensitive index (Sensex) of the BSE, which opened at 29,575.66 points, traded at 29,282.74 points (at 1.15 p.m.) - down 139.65 points or 0.47 per cent from the previous close at 29,422.39 points.
Foreign portfolio investors (FPIs) sold shares worth a net Rs 168.84 crore on Thursday, as per provisional data.
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Sector-wise, the S&P BSE healthcare index dipped by 115.80 points, followed by the automobile index, which slipped by 91.25 points, and the FMCG index, which fell by 90.57 points.
Other laggards were ITC (1.81 percent), Adani Ports (1.72 percent), Power Grid (1.44 percent), Wipro (1.36 percent), ICICI Bank (1.34 percent), Lupin (1.31 percent), M&M (1.28 percent), Coal India (1.12 percent), Maruti Suzuki (1.10 percent), HUL (1.08 percent) and SBI (0.97 percent).
NTPC, Asian Paints, L&T, Hero MotoCorp and ONGC too ended in green, rising up to 1.83 per cent. "Broad market indices like the BSE mid-cap and small-cap indices ended with bigger gains thereby outperforming the Sensex".
A firming trend at other Asian markets, tracking overnight gains at the Wall Street on revived hopes of USA tax cuts mainly accelerated buying activity on the domestic bourses, brokers said.
Asian markets were mostly mixed with Hong Kong's Hang Seng falling 0.06 per cent, while Japan's Nikkei rose 1.03 per cent. China's Shanghai Composite Index gained 0.03 percent.