Document outlines suspects' goals, 'mindset'

A rental car, believed to have belonged to one of the hijackers, was found at an airport in Portland, Maine.

WASHINGTON (CNN) -- A document tied to at least two of the suspected hijackers contains reminders and "rules of engagement" for carrying out a strike against the enemy, a law enforcement source said.

"It seemed like it was written to put them into a zone ... a certain mindset ... to carry out the mission," said the source.

The document was found in a car left behind at the airport in Portland, Maine, where two of the suspected hijackers -- identified by U.S. investigators as Abdul Aziz al-Omari and Mohamed Atta -- boarded a flight to Boston September 11. In Boston, law enforcement sources believe, the two got on board American Airlines Flight 11, which later slammed into the World Trade Center.

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The photocopied document was originally handwritten in Arabic, the source said. It includes the instruction "to strike your enemy above his neck" and appears to be a sort of self-reminder to the hijackers.

The document, several pages long, also includes rules, such as "be very punctual, how to handle yourself at a taxi stand, how to dress," as well as "how to act in certain situations," the source said.

It ended with a common Muslim prayer or greeting repeated more than once, something along the lines of "praise to Allah," the source said.

The source said that a translator helped decipher the document, but some of it "was unintelligible."

-- From CNN Correspondent Susan Candiotti