The International Monetary Fund warned of <A HREF="http://news.zdnet.com/2100-1009_22-6094634.html?tag=zdnn.alert">a jump in the number of fraudulent emails</A> and communications claiming to be from or affiliated with the Washington-based multilateral lender. There has been an apparent spike in such messages recently involving people in the United States targeting recent immigrants and people in cities, an IMF official said. The IMF said U.S. authorities have been informed.