The broader-based National Stock Exchange index Nifty fell by 43.20 points, or 0.71 percent, to 6,045.85.
Mumbai: Erasing early gains, BSE benchmark Sensex on Thursday lost 132 points to close at a fresh one week low as investors booked profits in bluechips led by TCS and Infosys after these IT majors posted smart quarterly numbers.
After opening higher and rising to as much as 20,621.3, the 30-stock index failed to maintain the upward momentum and closed lower by 132.11 points or 0.64 percent at 20,415.51. This is Sensex's biggest single-day fall in this month.
Similarly, the broader-based National Stock Exchange index Nifty fell by 43.20 points, or 0.71 percent, to 6,045.85. The SX40 index on the MCX Stock Exchange closed lower by 49.26 points at 12,179.29.
Brokers said the selling pressure was confined to recent gainers led by IT sector, which had surged on attractive quarter earnings.
They said a mixed trend in the Asian region and lower opening in European markets as Chinese rating company downgraded the American government's debt, further influenced the sentiment.
Out of the 30 BSE index components, 18 stocks declined and 11 gained, while one stock -- State Bank of India -- remained unchanged.
Major Sensex losers were Tata Consultancy Services, Infosys, Wipro, Larsen and Toubro, Cipla, Tata Motors, Maruti Suzuki, ICICI Bank, HDFC Bank, Dr Reddy's Lab and NTPC.
Sectorally, the IT sector index suffered the most by losing 3.59 percent, followed by Teck index by 2.61 percent. Capital goods index lost 2.30 percent and auto index by 1.20 percent.