The BSE benchmark Sensex on Wednesday erased initial gains to trade lower by 139 points, as investor indulged in booking profits on reports of slowing industrial production.

The sensitive index, Bombay Stock Exchange or Sensex fell by 139.95 to 19,056.39 at 1130 hrs, after rising to 19,379.55 in the opening trade.

Similarly, the broad-based index, National Stock Exchange or Nifty lost 38.75 points to 5,715.35. It opened higher at 5,815.75.

Market sentiment turned weak after reports of Index of Industrial Production (IIP) declining to 2.7 per cent in November 2010, compared to 11.3 per cent in the same month a year-ago, traders said.

They said a mixed pattern of trade in the Asian region further influenced the market sentiment.