A new version of the September 11 commission's report on the four hijacked flights was released with recently declassified information about terrorist threats and holes in airport security before the attacks.

At the request of the September 11 commissioners, the Bush administration declassified much, but not all, of the material it had blacked out before turning the report over to the National Archives in January. The new version released on Tuesday provides fresh details on the repeated warnings about al-Qaeda and its desire to attack airlines in the months before September 11, 2001.

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For example, on page 61, a previously classified section shows that the Federal Aviation Administration's intelligence unit received 'nearly 200 pieces of threat-related information daily from US intelligence agencies, particularly the Federal Bureau of Investigation, Central Investigative Agency and State Department.'

Also declassified was the conclusion that the domestic aviation system had, since 1996, 'operated at a security level that was, in effect, a permanent code orange.'

The new report revealed that the civil aviation system was under 'Aviation Security Alert Level III' on September 11, which meant that screeners were supposed to pat down suspicious passengers, but only those who had checked their baggage.

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