The FBI says it has thwarted a planned terrorist attack on John F. Kennedy International Airport Saturday.

Three men have been arrested and a fourth, Abdel Nur, is being sought in the Caribbean.

Federal officials say the men planned to detonate a fuel supply line that carried fuel from Linden, New Jersey to the Queens airport. Officials say the plot was being engineered to kill thousands and economically devastate the country.

FBI officials say that the plot planned to also target citizens in Queens since the fuel line runs through residential neighborhoods in the area.

One of the alleged terrorists, Russell Defreitas, is a retired JFK employee and U.S. citizen. Officials say he first developed his attack over ten years ago during his tenure as a cargo handler. He is currently in custody in Brooklyn.

Abdul Kadir of Guyana and Kareem Ibrahim of are in custody in Trinidad while authorities hunt a fourth man, Abdel Nur.

Roslynn Mauskopf, United States Attorney of eastern New York, said the plot is one of the most chilling terrorist plots imaginable.

"The devastation that would be caused had this plot succeeded is just unthinkable,? said Mauskopf. ?What this case does is once more underscores the fact that New York City is very much on the top of the terrorist target list.?

Federal investigators say they first learned about the plot back in January 2006. They soon infiltrated the group with the help of an informant.

AP wire reports contributed to this article.