WASHINGTON — Documents seen by FOX News suggest a conflict of interest may exist between Kofi Annan's (search) son, the Swiss company he worked for and the United Nations. Congressional investigators are examining those records and thousands of pages of others as part of their probe into the controversial U.N. Oil-for-Food (search) program. FOX News was permitted to review some documents but not make copies. Kojo Annan (search), the son of the U.N. secretary general, claims he has never been involved directly or indirectly with any business related to the United Nations. And Cotecna Inspection S.A., the company Kojo worked...