New York City ? The investigation into the thwarted plot to bomb Kennedy International Airport is widening beyond the four men in custody, with more suspects sought outside the U.S. for their suspected roles, a law enforcement official said Friday.

The defendants identified last weekend were “just a piece of it,” the official told The Associated Press on the condition of anonymity because of not being authorized to speak publicly. “We are definitely seeking more players. We are targeting others overseas.”

The official declined to provide details about the possible suspects, or in what countries they are being sought.

Law enforcement officials, through the use of an informant, were able to undermine the airport plot in its early stages.