WASHINGTON -- Unheeded warnings, poor planning and apathy in recognizing the scope of Hurricane Katrina's destruction led to the slow emergency response from the White House down to local parishes, a House investigation concludes.

The 600-page report by a special Republican-dominated House inquiry into one of the worst natural disasters in U.S. history concluded that late state and local evacuation orders exacerbated an untrained and inexperienced force of federal emergency responders.

It also said President Bush received poor and incomplete counsel about the crisis unfolding in the Gulf Coast.

Overall, the House report said, the federal government's response to Katrina was marked by "fecklessness, flailing and organizational paralysis."

"Our investigation revealed that Katrina was a national failure, an abdication of the most solemn obligation to provide for the common welfare," said a summary of the scathing report obtained Sunday by The Associated Press.

"At every level -- individual, corporate, philanthropic, and governmental -- we failed to meet the challenge that was Katrina," the report concluded.

"In this cautionary tale, all the little pigs built houses of straw."

The House findings mark the first of two congressional inquiries and a White House review of the storm response expected over the next six weeks.

On Monday, the Senate Homeland Security and Governmental Affairs Committee was to continue its own investigation into the Aug. 29 storm response by examining potentially widespread abuse in federal emergency cash assistance programs for disaster victims. Up to 900,000 of 2.5 million applicants received aid based on duplicate or invalid Social Security numbers, or false addresses and names, congressional investigators found.

"Everything that we have found ... confirms exactly the indictment of the House Republicans," Sen. Joseph Lieberman of Connecticut, that committee's top Democrat, said Sunday. "It's shocking and it is unsettling."

Excerpts released from the House report, which issued a total of 90 separate findings, spreads the blame through all levels of government.

Among the conclusions:

--Late decisions by New Orleans Mayor Ray Nagin and Louisiana Gov. Kathleen Blanco to issue mandatory evacuations in the New Orleans area led to deaths and prolonged suffering.

--The White House was unable to effectively sort through conflicting reports about levee breaches and other disaster developments, preventing rapid relief.

--The Federal Emergency Management Agency suffered from a lack of trained and experienced personnel.

--Military assistance was invaluable, but the military failed to coordinate with state, local and other federal assistance organizations.

--Government officials at all levels failed to take into account lessons learned from a 2004 fictional storm exercise, dubbed Hurricane Pam, that was supposed to specifically test the region's readiness.

The House investigation criticized Homeland Security Secretary Michael Chertoff's actions, saying his overall responsibilities for the federal disaster relief were fulfilled "either late, ineffectively or not at all."

The special report concluded that Chertoff unnecessarily delayed naming a top federal coordinator for relief efforts and the activation of an internal disaster management group. More prompt action by Chertoff would have quickened the relief effort, the report said.

The House report also faulted Chertoff for not following a response plan specifically for catastrophic disasters.

In blistering testimony Friday, former FEMA director Michael Brown said Chertoff had marginalized the agency's role in the Homeland Security Department, which he said was focused more on fighting terrorism than preparing and responding to natural disasters.

In an interview Sunday, the department's deputy secretary, Michael Jackson, called Brown's testimony "an unconscionable misrepresentation" and said the former FEMA chief was disgruntled with having to report to Chertoff instead of directly to President Bush.

Chertoff "trusted his incident commander," Jackson said. "What we saw Friday was an acknowledgment by the incident commander that he had betrayed that trust and blatantly disregarded his obligations to his boss and responsibilities."

An investigator who helped write the House report said Sunday that Chertoff was no more to blame for the sluggish response than other government authorities.

White House spokesman Trent Duffy said Bush was "engaged and fully involved in the response efforts," noting that the president declared Katrina a disaster before the storm hit and make a personal plea for citizens to evacuate.

"He knew full well the danger of the storm and the threat it posed," Duffy said Sunday night. "But when he wasn't satisfied, he was the first to stand up and take responsibility."

The special House panel, chaired by Rep. Tom Davis, R-Va., was boycotted by Democratic leaders who called for an independent inquiry of the government's failings similar to that of the 9/11 Commission that investigated the Sept. 11, 2001 terror attacks.

But two Democrats who participated in the House inquiry, while widely praising the draft report, said it should have called for removing Chertoff from his job.

"The Department of Homeland Security needs new and more experienced leadership," said Reps. Charlie Melancon and William Jefferson, both of Louisiana.

Details of the House findings were first reported in Sunday's editions of The Washington Post.