Mumbai: The Bombay Stock Exchange (BSE) benchmark Sensex tumbled by 208 points in opening trade Monday, extending its three-session losing streak on concerns over slowing industrial growth amid a weakening trend on other Asian bourses and persisting worries about the European debt crisis. The 30-share Sensex, which has lost over 511 points in the past three sessions, plunged by 208.42 points, or 1.35 per cent, to 15,282.93 in opening trade. In a similar fashion, the wide-based National Stock Exchange Nifty index declined by 69.55 points, or 1.50 per cent, to 4,582.05. All the sectoral indices, led by banking, were trading in the negative zone, with losses of up to 2.78 per cent. Brokers said the market sentiment was dampened by the country''s lowing economic growth, in addition to a weakening trend on other Asian bourses amid a lack of a progress on resolving the euro zone debt crisis. In the Asia region, Hong Kong''s Hang Seng index was down by 2.52 per cent and Japan''s Nikkei index lost 1.47 per cent in morning trade Monday. The US Dow Jones Industrial Average ended 0.02 per cent lower in the previous session on Friday.