Washington: Sharply criticising Central Intelligence Agency (CIA) and the Federal Bureau of Investigation (FBI), the final report of a Congressional inquiry into September 11 terror strikes released on July 24 says while the former failed to act on intelligence it had about the hijackers, the latter was unable to track al-Qaida in US.

Even had these and many other failures not occurred, no evidence surfaced in the probe by the House and Senate intelligence committees to show that the government could have prevented the attacks that killed more than 3,000 people in New York, Washington and Pennsylvania, says the report.

White House spokesman Scott McClellan said the report "confirms the importance of the strong, aggressive stance we have already taken to better protect the American people at home and abroad".

The report makes clear there were ample warning signs that Osama bin Laden was planning attacks against the United States, and several opportunities to learn about the plot were missed by intelligence and law enforcement agencies.

The "best chance to unravel the September 11 plot" was lost because intelligence agencies failed to let the San Diego FBI office know that two men were suspected terrorists - and would later turn out to be among the hijackers, according to the report.

National Security Agency (NSA), the nation's key signals intelligence agency, intercepted conversations in early 1999 indicating that two future hijackers were connected to a suspected al-Qaida facility in the Middle East, but that information was not passed on to other agencies.

PTI