WASHINGTON, June 4 (IslamOnline & News Agencies) - The U.S. Congress Tuesday launched a series of closed-door investigative hearings into how federal agencies dealt with incoming information prior to Sept. 11 attacks. However, President Bush expressed concern that congressional probes might take government experts away from their central job of preventing another attack.

At the center of the furor is the Federal Bureau of Investigation's (FBI) mishandling of agent requests and information that suggested future attacks on the United States, and the Central Intelligence Agency's (CIA) failure to share intelligence on two of the September hijackers, reported Agence France-Presse (AFP).

"It is essential that we get this sorted out," House Majority Leader Dick Armey told reporters.

The private hearings led by a joint House-Senate Intelligence panel, which could last for months, kick off Tuesday afternoon inside a windowless, soundproofed and secured room in the Capitol building.

Meanwhile, Bush expressed “concern” over the congressional probes, while touring the headquarters of the top-secret National Security Agency (NSA), a massive intelligence-gathering operation that essentially eavesdrops on the world.

"What I am concerned about is tying up valuable assets and time and possibly jeopardizing sources of intelligence," Bush said, U.S. daily Washington Post reported Tuesday.

The NSA is located at the Fort Meade Army base, a sprawling and heavily guarded military facility between Washington and Baltimore, Maryland. The NSA is housed in a tall modern building faced with reflecting black glass.

Bush gave a pep talk to employees that was closed to the press. The NSA work force represents an unusual combination of specialties: analysts, engineers, physicists, mathematicians, linguists, computer scientists and researchers, the Post said.

Bush told reporters it was clear the FBI and the CIA were not communicating properly before Sept. 11. He added, however, that the two agencies are now in much closer contact. One of the main criticisms of the U.S. security agencies has been that they failed to share intelligence.

Bush said he saw no evidence suggesting the United States had information that would have allowed it to prevent the attacks on New York and Washington, in which some 3,000 people were killed.

"I have seen no evidence to date that said this country could have prevented the attack," added the President, standing beneath a banner that said: "We won't back down. We never have. We never will."

As the FBI and CIA traded blame in the newspapers, Bush said he was less concerned about finger-pointing and more concerned about congressional investigations turning into distractions.

"Yes, I am concerned about distractions from this perspective. I want Congress to investigate, but I want a committee to investigate, not multiple committees to investigate ... because I don't want to tie up our team when we were trying to fight this war on terror," he said.

On Thursday, June 6, meanwhile, the Senate Judiciary committee will open the first of several hearings open to the public.

"I think the number one objective is public awareness of what happened and to make sure that we take the necessary steps to improve our national security so it doesn't happen again," Porter Goss, chairman of the House Select Intelligence committee and a former CIA agent, told NBC Tuesday morning.

In what is likely to be star-making testimony, longtime FBI attorney Coleen Rowley, who sent a blistering 13-page memo excoriating actions of her bureau to both FBI director Robert Mueller and members of Congress, is to appear Thursday before the panel headed by Vermont Democrat Patrick Leahy.

She will likely provide a broad overview of how inefficiencies at both the FBI headquarters in Washington and the Minneapolis field office conspired to refuse a search warrant for the possessions of Zacarias Moussaoui - a French national suspected as the would-be 20th hijacker, who has been in federal custody since August.

Embattled FBI director Robert Mueller and CIA chief George Tenet are due to face lawmakers in mid-June to explain what broke down on and before the September 11 strikes, the single-largest attack on U.S. soil.

"They could have done better, they should have done better and I think we will find ways to improve the system, and that will be one of the beneficial outcomes of our efforts that will go on all summer," Goss said.