WASHINGTON, April 8 (Xinhua) -- The U.S. Federal Reserve said Tuesday it auctioned 50 billion U.S. dollars in short-term loans to cash-strapped banks on Monday to combat a persistent credit crunch.

    This was the central bank's ninth auction aimed at injecting more money into the U.S. banking system since mid-December 2007, when the Fed established its Term Auction Facility to deliver short-term funds to banks that are in need of liquidity.

    The series of auctions so far have pumped 310 billion dollars into the banking system.

    The latest auction produced an interest rate of 2.82 percent, higher than the rate of 2.62 percent generated in the previous one, which was held on March 24 and provided 50 billion dollars to banks.

    The Federal Reserve announced in late March that it would auction 100 billion dollars in April, continuing its efforts to deal with the effects of a credit crisis.

    The other auction in April will be held on April 21 and will offer another 50 billion dollars.

    Earlier last month, the Fed said it would continue the auctions "for at least the next six months unless evolving market conditions clearly indicate that such auctions are no longer necessary."