WASHINGTON (CNN) -- A security scare forced a flight from New York to Madrid to turn around soon after takeoff.

The plane returned to John F. Kennedy Airport Thursday night. Investigators eventually determined there was no threat and the plane was cleared to head to Spain.

Delta flight 126 took off for Madrid just after 8pm. About an hour into the flight, suspicious wires were found sticking out of straws on the toilet and sink in one of the lavatories. The pilots turned the plane back to JFK.

A woman who was having trouble breathing at the moment the wires were discovered, was at one point suspected of being a decoy for a man who had been spotted in the lavatory. From inside the locked cockpit the pilot radioed emergency crews.

“She is the one who is supposed to be the decoy that keeps looking at the gentleman that was playing with the possible explosive device in the lavatory,” said the pilot.

“Roger. What kind of aliments were they complaining of?” said the emergency crew.

“She is weak and on oxygen. I don't know for what reason they think that they may be a ploy and a team, but we were just overhearing what we could hear on the interphone. We are not back there 'cause we have the cockpit secure,” said the pilot.

“That's from the FAMs. They are worried that it may be actually a real team onboard, and we'd like to get security on the airplane as soon as we can,” said the pilot.

‘FAMs’ stands for Federal Air Marshals. FAMs are the security officers who fly undercover, revealing themselves to passengers only in an emergency.

“Just be aware we have 4 FAMs in the back of the aircraft. Two of them are armed,” the pilot told the emergency crew.

Despite what the pilot told rescue crews, the TSA won't confirm that there were Air Marshals on this flight, why there were four of them or why two were apparently unarmed. Police questioned the man believed to have used the lavatory and the woman who had difficulty breathing. After an extensive sweep with bomb-sniffing dogs, authorities found no evidence of explosives or any other threat. No one was arrested and after nearly six hours, the passengers boarded another plane for Madrid that took off at 3:10 am.

There are some things we still don't know about what exactly went down on that plane, like where those wires came from and exactly how they ended up in the lavatory. This incident goes to show that pilots will take any potential threat to an aircraft very seriously.