Mumbai: The BSE benchmark, Sensex, extended gains for the second straight day by adding over 83 points in early trade on increased buying by funds and retail investors amid covering-up of short positions by speculators. The 30-share index, which had gained 199.02 points in the previous session, added another 83.20 points or 0.51 percent, to 16,500.04 with all the sectoral indices led by auto were trading in positive zone with gains up to 0.92 percent. The wide-based National Stock Exchange index, Nifty, regained crucial 5,000 points level by rising 19.70 points or 0.40 percent, to 5,005.35. Brokers said besides value buying by funds and retail investors at selective stocks, having strong fundamentals, covering-up of short positions ahead of Thursday's monthly expiry in the derivatives segment also influenced the trading sentiments. They said the mood was also helped by global rating agency Moody's comment that the sliding rupee will not impact India's sovereign ratings. In the Asian region, the Japan's Nikkei was down 0.06 percent, while Hong Kong's Hang Seng marginally up by 0.18 percent in the morning trade on Tuesday. The U.S. markets remained closed on Monday for Memorial Day holiday.