Tracking global markets, the Bombay Stock Exchange benchmark index on Wednesday fell by more than 99 points in early trading over funds selling in blue-chip stocks.
The BSE-30 share index, Sensex, which had gained 62.75 points on Tuesday, fell by 99 points to 15,632.71 in the first five minutes of trading.
Similarly, the National Stock Exchange's wide-based Nifty was down by 52 points at 4568.75.
Stock brokers said reports of weakening trend in the international markets mainly triggered selling by funds on the domestic bourses.
They said ahead of Thursday's expiry of July contracts in the derivatives segments also dampened the market sentiment.