Erasing its initial gains, the Bombay Stock Exchange benchmark Sensex today dropped by about 296 points to 19,091 in a volatile session on selling by funds in fundamentally strong stocks led by Infosys Technologies amid a weak global trend.

The Sensex, which had lost 310 points in the previous session, rolled down further by 295.65 points to 19,091.17 as Infosys — the second-most heavy index-linked stock — remained weak post lower-than-expected earnings announced last week.

The gauge initially rose to 19,649.22 and touched the day’s low of 19,071.47.

In a similar fashion, the National Stock Exchange index Nifty, after a higher start of 5,897.90, closed lower by 95.45 points to 5,729.10.

Infosys dipped further today as its stock was cut to “neutral” from “outperform” by Credit Suisse Group on “disappointing” results and “poor margin guidance”. The company, along with TCS, pulled down the IT index.

Besides, the Asian markets and the European market were weak on mounting inflation around the globe amid Europe’s sovereign debt crisis rearing head again.

The information technologies index fell by 2.73 per cent to 6,087.88, as Infosys slid 2.8 per cent to Rs 2,905.20, extending the 9.6 per cent slump on April 15. TCS fell by 3.43 per cent to Rs 1,149.70. The two companies have a combined 14 per cent weighting in the Sensex.

HDFC Bank lost amid concerns that the Reserve Bank of India might raise rates further to cool inflation. The stock dropped by 1.89 per cent to Rs 2,315.70, ICICI Bank 1.73 per cent to Rs 1,082.20 and State Bank of India fell by 1.8 per cent to Rs 2,752.95.

The most-heaviest on the Sensex, Reliance Industries, fell by 0.81 per cent to Rs 1,010.15 on concerns that the rising crude oil prices might reduce its revenue.

As the selling pressure spread over a broad front, the mid-cap index fell by 1.29 per cent to 7,116.12 and small-cap index by 0.81 per cent to 8,737.06.