The federal government mistakenly made public a 266-page report, its pages marked highly confidential," that gives detailed information about hundreds of the nation's civilian nuclear sites and programs, including maps showing the precise locations of stockpiles of fuel for nuclear weapons. The publication of the document was revealed Monday in an online newsletter devoted to issues of federal secrecy. It ... prompted a flurry of investigations in Washington into why the document had been made public. On Tuesday evening, after inquiries from The New York Times, the document was withdrawn from a Government Printing Office Web site. The information, considered confidential but not classified, was assembled for transmission later this year to the International Atomic Energy Agency as part of a process by which the United States is opening itself up to stricter inspections in hopes that foreign countries, especially Iran and others believed to be clandestinely developing nuclear arms, will do likewise. President Obama sent the document to Congress on May 5 for Congressional review and possible revision, and the Government Printing Office subsequently posted the draft declaration on its Web site. Steven Aftergood, a security expert at the Federation of American Scientists in Washington, revealed the existence of the document on Monday in Secrecy News, an electronic newsletter he publishes on the Web. Mr. Aftergood expressed bafflement at its disclosure, calling it "a one-stop shop for information on U.S. nuclear programs." The report lists many particulars about nuclear programs and facilities at the nation's three nuclear weapons laboratories - Los Alamos, Livermore and Sandia - as well as dozens of other federal and private nuclear sites.