Rising for the third day in a row, the BSE Sensex gained 65 points in early trade today on sustained buying by funds and retailers amid a firming trend in Asian region. The 30-share barometer, which had gained almost 404 points in the previous two sessions, added 65 points, to nearly 17,667.Similarly, the wide-based National Stock Exchange Nifty moved up by over 20 points, to 5,357.