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FAA: Nine hijackers singled out for screenings

WASHINGTON (CNN) -- Transportation authorities singled out nine of the 19 hijackers in the September 11 attacks for special security screenings before they boarded their flights that morning, a Federal Aviation Administration spokesman said Saturday.

Under the enhanced precautions, airport security screened the hijackers' checked bags for weapons and explosives -- a measure that was not mandated for most passengers last fall.

The hijackers' carry-on bags would have been checked at the same security checkpoints through which all passengers pass.

At the time of the attacks, the box-cutting knives the hijackers used to take control of the planes would have been allowed to be taken onto the aircraft.

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The FAA spokesman, who asked not to be identified, said all proper procedures were followed regarding the screening of the hijackers.

According to the Washington Post, which first reported the story Saturday, a computerized screening system chose six of the hijackers for the tightened security measures.

Two others were selected because of irregularities in their identification documents, U.S. officials told the Post.

The ninth hijacker was listed in travel documents as traveling with one of the men singled out because of his identification, the Post reported.

Law enforcement and aviation officials refused to discuss other aspects of the screening, including which hijackers were selected, whether they were interrogated or whether the knives were discovered at security checkpoints, according to the Post.