The Sensex at the Bombay Stock Exchange failed to maintain initial gains and was quoted lower by 152 points to 20,708 in late morning trade. The fall attributed to fresh selling pressure, mainly in banking, refinery, power, capital goods and realty sectors on fears of a slowdown in foreign capital inflows. Earlier, the 30-share index gained 158 points in the opening trade today.The National Stock Exchange index Nifty was down by 49 points to 6,168.