Mumbai: The Bombay Stock Exchange benchmark Sensex fell by over 261 points in opening trade on continued selling by funds and investors even as Infosys reported a 15.72 per cent jump in first quarter earnings on Tuesday morning.

Infosys Technologies' Q1 net profit rose 15.72 per cent to Rs 1,722 crore, while its revenue was up 20.76 per cent at Rs 7,485 crore.

Inspite of the good news, the 30-share Sensex, which opened 112 points lower, declined by 261.27 points, or 1.39 per cent, to 18,460.12 in the first few minutes of trade on Tuesday on sustained selling in stocks of IT, tech, realty, banking and metal companies.

In a similar fashion, the wide-based National Stock Exchange Nifty index slid by 80.65 points, or 1.43 per cent, to 5,535.45 points.

Infosys, the second most-weighted firm on the Sensex, was trading 5.52 per cent down at Rs 2,758 a share after dipping to Rs 2,660.55.

Brokers said funds and retail investors indulged in selling, largely in tandem with weakening trend overseas on escalating euro zone debt worries and even ignored the 15.72 per cent jump in first quarter earnings by Infosys.

In addition, off-loading of positions by participants ahead of the release of factory output data for the month of May later today also cast its shadow on the sentiment, they said.

In the Asian region, Hong Kong's Hang Seng Index was down 2.04 per cent, while Japan's Nikkei lost 1.41 per cent in morning trade on Tuesday. The Dow Jones Industrial Average in the US ended 1.20 per cent lower in Monday's trade.