US stocks tumbled more than 2% at today's opening, tracking global equities sharply lower as Japan's looming nuclear crisis looked set to thrust financial markets into a period of turmoil. The Dow Jones fell 2.17%, while the Nasdaq Composite index lost 2.67%. European shares fell to their lowest in more than 14 weeks today after Japan warned of significantly higher radiation levels following explosions at one of its quake-stricken nuclear power plants. London's FTSE was down 2.4% this afternoon while the Paris CAC dropped 3.7% and the Frankfurt DAX slumped 4.7%. Dublin's ISEQ index fell 3.1%. Earlier in Asian trade, Tokyo's stock market closed down more than 10%, with panicking investors dumping shares after the Japanese government said levels of radiation leaking from a stricken nuclear plant posed a threat to health. The main Nikkei index clawed back some ground from an earlier freefall to close down 1,015 points (10.6%) at 8,605. Authorities evacuated non-essential staff from the Fukushima Number One plant while people up to 10 kilometres from the exclusion zone were told to stay indoors. Corporate giants such as Toyota and Sony were again hit by selling as they have been forced to halt production across Japan. Toyota lost almost 5%, while Sony dropped more than 6%. The Bank of Japan pumped eight trillion yen ($97.8 billion) into the financial system to soothe shaken money markets following Japan's biggest earthquake, and a devastating tsunami expected to have claimed at least 10,000 lives. The move by the BoJ came after it said yesterday it would inject a record 15 trillion yen to help stabilise the short term-money market, making good on an earlier pledge that it would unleash 'massive' funds following the disasters. The BoJ also said it will double a five trillion yen asset purchase scheme to help buffer the economy from the shock of the catastrophes. The central bank's priority is to ensure that financial institutions in disaster-hit regions do not run out of funds. Over the weekend it provided them with 55 billion yen to ease the pressure before Monday's move. The government expects a 'considerable' economic impact from the huge earthquake and devastating tsunami that plunged the nation into what Prime Minister Naoto Kan called its worst crisis since World War II.