Mumbai: The BSE benchmark index Sensex fell by over 68 points in early trade as funds and retail investors booked profits amid a weak trend on other Asian bourses. The 30-share index, which had gained 40.73 points in the previous session, fell by 68.24 points, or 0.40 percent, to 16,849.84, with stocks of metals, realty and oil gas leading the fall. Similarly, the wide-based National Stock Exchange index Nifty declined by 17.40 points, or 0.34 percent, to 5,110.80. Brokers said besides profit-booking by speculators after yesterday's gains, a weak trend on other Asian markets following overnight losses at the US markets amid euro-zone debt concerns and soft U.S. corporate earnings mainly influenced the trading sentiment here. They said a cautious approach adopted by participants in the absence of any positive trigger and tomorrow's monthly expiry in the derivatives segment too dampened the sentiment. In the Asian region, Hong Kong's Hang Seng index fell by 0.97 percent, while Japan's Nikkei Index shed 0.91 percent in the morning trade today. The U.S. Dow Jones Industrial Average ended 0.82 percent lower in yesterday's trade.