The BSE benchmark Sensex today rose by over 48 points in early trade, extending gains for the fifth straight session on continued buying by funds and retail investors. The 30-share BSE index, which has gained nearly 332 points in the past four sessions, gained another 48.09 points, or 0.25 per cent, to 18,811. in the early trade. Similarly, the wide-based National Stock Exchange NiftyIndex moved up by 11.70 points, or 0.20 per cent, to 5,715.90.In the Asian region, Hong Kong's Hang Seng Index fell by 0.71 per cent and Japan's Nikkei Index was down by 0.44 per cent in the morning trade today. The US Dow Jones Industrial Average closed 0.15 per cent higher on Monday.