The Bombay Stock Exchange benchmark Sensex fell by nearly 103 points in opening trade today. In a similar fashion, the wide-based National Stock Exchange Nifty index declined by over 33 points to 5,293.Stocks of capital goods, metals, banking and auto companies remained under selling pressure and were mainly responsible for the Sensex's decline.Market experts attributed the fall in domestic equities to sustained selling by funds amid a weakening trend on other Asian bourses in tandem with overnight losses in the US market.In the Asian region, Japan's Nikkei index fell by 1.20 per cent, while Hong Kong's Hang Seng index lost 2.03 per cent in early trade on Tuesday. In the US, the Dow Jones Industrial Average down 2.26 per cent in yesterday's trade.