TOKYO: Japanese stocks tumbled Monday and the central bank pumped a record amount of cash in a bid to soothe money markets shaken by Japan's biggest ever earthquake, a devastating tsunami and a nuclear emergency. The Bank of Japan (BoJ) said it would pump in a record 15 trillion yen ($184 billion) to help stabilize the short term-money market, making good on its pledge Sunday that it would unleash “massive” funds following the quake. An additional 6.8 trillion yen will be deployed Tuesday and Wednesday, including 3 trillion in bond purchases, bringing the total available to 21.8 trillion yen. The BoJ will also double a five trillion yen asset purchase scheme to help buffer the economy from the shock of Japan's strongest ever quake, and left its key rate at between zero and 0.1 percent. 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 the Second World War. The priority of the central bank 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 fresh fund move. Monday's injection was the BoJ's first since European sovereign-debt fears pushed up the yen steeply in November and weighed on Tokyo shares, when it injected same-day funds to boost confidence. – Agence France