The Bush administration built an unprecedented surveillance operation to pull in mountains of information far beyond the warrantless wiretapping previously acknowledged, a team of federal inspectors general reported Friday, questioning the legal basis for the effort but shielding almost all details on grounds they're still too secret to reveal. The report, compiled by five inspectors general, refers to unprecedented collection activities" by U.S. intelligence agencies under an executive order signed by President George W. Bush after the Sept. 11, 2001, terror attacks. Just what those activities involved remains classified, but the IGs pointedly say that any continued use of the secret programs must be "carefully monitored." The report says too few relevant officials knew of the size and depth of the program, let alone signed off on it. They particularly criticize John Yoo, a deputy assistant attorney general who wrote legal memos undergirding the policy. His boss, Attorney General John Ashcroft, was not aware until March 2004 of the exact nature of the intelligence operations beyond wiretapping that he had been approving for the previous two and a half years, the report says. Most of the intelligence leads generated under what was known as the "President's Surveillance Program" did not have any connection to terrorism, the report said. The only piece of the intelligence-gathering operation acknowledged by the Bush White House was the wiretapping-without-warrants effort. Although the report documents Bush administration policies, its fallout could be a problem for the Obama administration if it inherited any or all of the still-classified operations.