The Bombay Stock Exchange benchmark Sensex wiped off early gains at 14,447.96, lower by nearly 74 points at mid-session on Monday on profit booking.
The 30-share index, which gained nearly 150 points in the opening session, fell by 73.93 points at 1315 hrs with stocks of oil and gas, and power sectors reacting to profit-taking by funds and retail investors.
In a similar manner, the wide-based National Stock Exchange index Nifty slipped 54.05 points at 4,259.55 at the same time.
Stockbrokers said emergence of profit-taking at improved levels and weak opening at the European stock markets mainly reversed an early firming trends on the domestic bourses.
Major losers which dragged the Sensex down were Reliance Industries down 2.60 per cent at Rs 1,986.50, RPL 2.76 per cent at Rs 123.25, Reliance Infra 2.32 per cent at Rs 1,233, Tata Steel 0.77 per cent at Rs 408.60 and Sterlite Industries 1.52 per cent at Rs 597.50.