Tokyo -
Japan's key Nikkei 225 Stock Average fell to a four-year low Monday on worries about the financial crisis, despite US Congressional approval of a Wall Street bail-out.
The benchmark Nikkei index ended the morning trading at 10,544.33, down 393.81 points, or 3.60 per cent.
The broader Topix index of all first-section issues also fell 42.44 points, or 4.05 per cent, to 1,005.53.
It is the first trading day in Tokyo since the US Lower House approved Friday, after tough negotiations, the 700-billion-dollar rescue package for the financial sector.