Asian stocks fell on Friday, extending Thursday's heavy losses, as investors fretted about the possibility of lower global growth. So Hong Kong's Hang Seng slipped 1.4%; China's Shanghai Composite index lost 0.4%; Singapore's Strait Times index dropped 0.8%; and South Korea's Kospi index slumped 5.7%. Japan's markets were closed for a holiday.But, stock markets in Europe, rebounded from a two-year low as a pledge from the Group of 20 to address risks to the economy outweighed a slide in commodity producers. But investors remained jittery, amid ongoing Group of 20, IMF and World Bank annual meetings.Greek banks led the losers, after downgrades by ratings firm Moody's Investors Service. So key European indices, London's FTSE-100, France's CAC-40 and Germany's DAX were trading higher between 0.4% and 0.6% in intra-day trade.