Teh American news television station, CNN, has released what it claims are the names of the 18 hijackers who are believed to have commandeered four commercial airliners in Tuesday's attacks.
It says it obtained the names from FBI documents. All names listed by CNNare Middle Eastern.
It has been reported that all but one of ten people arrested earlier in John F. Kennedy International and LaGuardia airports in New York have been released.
A police source had confirmed 10 people were taken into custody at the airports after they reopened yesterday.
But US Senator Mr Joseph Biden told CNNthe men arrested at New York airports were innocent.
He said one was a pilot who was also carrying his brother's ID. The others were genuine Boeing workers of their way to a West Coast conference and one was a "screwball".
Earlier, passengers on a Los Angeles-bound flight out of Kennedy Airport said police in combat gear stormed the plane and apprehended people.
It had been thought that one of those detained had been carrying false pilot's identification.
It was also reported that some of the people taken into custody were carrying knives similar to those used in Tuesday's hijackings.
It now seems those arrested may have been legitimate employees of an airline.