ABC’s Good Morning America:

U.S. authorities are scrambling to sort through information that the CIA developed in the past 24 hours indicating that at least three individuals entered the U.S. in August by air with the intent to launch a vehicle-borne attack against Washington, D.C. or New York around the anniversary of 9/11, according to intelligence officials.

Officials say the alleged terror plot was initiated by new al Qaeda chief Ayman al-Zawahiri, Osama bin Laden’s successor, who had pledged to avenge bin Laden’s death earlier this year in a U.S. raid.

Intelligence and law enforcement officials told ABC News that at least one of the individuals is a U.S. citizen and one official said that two of the individuals may have had U.S. documentation — whether green cards or passports was unclear.

The threat was described as specific and credible by federal officials.

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