The alleged plot involves taxi cabs used as weapons targeted at JFK Airport and Los Angeles International. And the source says in the case of JFK, 3 local college students would wear and detonate suicide vests in the first wave of the attacks.
The Department of Homeland Security issued an alert bulletin stating that "According to unverified information from a volunteer who made large and specific demands for money and whose access was unclear, our service received info that as of early September 2013 Ayman al-Zawahiri was allegedly in the final stages of coordinating an attack on Los Angeles International Airport and Kennedy Airport."
"There's a threat assessment. It goes from low to high based on the credibility of information," said Nicholas Casale, a security expert.
And this taxi cab airport plot is low on the threat level because of the questionable motive of the source.
"The first thing he says he want money and the more money you give him the more he'll tell you. That diminishes his credibility," adds Casale.
The federal authorities released a statement saying "At this time, the FBI continues to assess the information but there remains no specific or credible threat."
And a Port Authority Police source says it's getting no more attention than a bomb threat which the airports get all the time, yet can never be ignored.
Meantime, a Los Angeles International Airport security screener has been charged with making threats hours after he quit his job that led to the closure of some terminals.
Court records show 29-year-old Nna Alpha Onuoha was charged Wednesday with one count each of making a false threat and making threats affecting interstate commerce.
If convicted of both counts, he could face up to 15 years in prison.
Federal officials say Onuoha made two calls to LAX after resigning and told officials to evacuate terminals. Parts of the airport were cleared and searched. Nothing was found.
A website has a picture of Onuoha and rambling letters attributed to him that promise something more devastating than the 9/11 attacks.