The investigation into the thwarted plot to bomb John F. 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.

The four suspects made trips to the airport, took video and photographs, drew diagrams and collected information. They then hoped to shop their information to individuals with the capacity to pull off their stated plan of causing "greater destruction than the Sept. 11 attacks," the official said.

According to court documents, the men sought the help of Jamaat al Muslimeen, or JAM, a Muslim organization based in Trinidad -- a known violent group involved in killings, kidnappings and weapons trafficking over the past two decades. The group staged a coup attempt in 1990, storming the Trinidad Parliament building and taking the prime minister hostage.

Some experts have called the plot far-fetched, saying it would have been virtually impossible to achieve the kind of destruction the suspects envisioned. But the official said that if the men had lined up with people who had the right resources, the plans could have been carried out in a short period of time.

Alleged mastermind Russell DeFreitas, a U.S. citizen from Guyana, hatched the plan when he worked as a cargo employee at JFK 10 years ago, authorities said. He is being held in New York on conspiracy charges. His alleged co-conspirators, two citizens of Guyana and one from Trinidad, are in jail in Trinidad and were expected to fight extradition to New York.

Defreitas' attorney, Drew Carter, was out of town and did not immediately return phone messages.

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