Delta Flight Detained, FBI Investigates

W A S H I N G T O N, Oct. 13 -- A New York to Amsterdam flight was canceled when the airline alerted authorities about four men who purchased or attempted to purchase one-way tickets, prompting the FBI to investigate.

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The Delta Air Lines flight was scheduled to depart from New York's John F. Kennedy International Airport on Friday evening. Two men were detained before the flight and held by immigration by immigration authorities after questions arose about their travel documents, according to the Associated Press.

The FBI told the Associated Press that two of the men were detained before the flight Delta Air Lines flight's scheduled departure from New York's John F. Kennedy International Airport Friday evening, and held by immigration authorities after questions arose about their travel documents.

Suspicions were raised after two men bought one-way tickets from a New York City travel agency, paying with cash and leaving an apparently bogus phone number, ABCNEWS has learned. A short time later, two more men, described as Middle Eastern, arrived at the travel agency also seeking one-way tickets for that night's flight. When the travel agent became suspicious and started to make a phone call, the two men quickly left the building.

"I'm not going to get into any detail other than the fact that we were conducting an investigation," Barry Mawn, head of the FBI's New York office, said at a press conference today. "The joint terrorism task force, out at the airport, there were some individuals that, as far as their ticketing and their status, we were checking, and that is ongoing."