NASHUA, N.H. (AP)  The two hijacked jets that demolished the World Trade Center nearly crashed into each other while heading to their target, according to a Federal Aviation Administration employee at a regional control center. "The two aircraft got too close to each other down by Stewart" International Airport in New Windsor, N.Y., about 55 miles north of New York City, the employee told The Telegraph of Nashua. It wasn't clear how close they got after they left Boston 15 minutes apart Tuesday morning, both headed for Los Angeles. Hijackers gained control of American Airlines Flight 11 around Gardner, Mass., said the employee, who spoke on condition of anonymity. Gardner is about 45 miles northwest of Boston.

"American was just flying around, doing what it wanted," the employee said of the jet's approach to New York. United Airlines Flight 175 remained in the hands of its pilots until it reached Albany, N.Y., the employee said. Albany is about 140 miles north of New York. The controller noticed American Flight 11 was having difficulties when its transponder, the device that sends an electrical radar pulse to air traffic control centers, shut off, the employee said. At that point, the plane veered from its course, the employee said. Soon after, the controller realized a hijacker stood in the cockpit when the plane's captain, John Ogonowski of Dracut, Mass., turned on his microphone, the employee said. The pilot was apparently triggering a "push-to-talk button" on the aircraft's steering wheel, a feature that enables pilots to have their hands on the controls while communicating, another employee told The Christian Science Monitor. That let controllers hear much of what was said and other cockpit noises. "The button was being pushed intermittently most of the way to New York," the employee said. "He wanted us to know something was wrong. When he pushed the button and the terrorist spoke, we knew. There was this voice that was threatening the pilot, and it was clearly threatening." Through the radio connection, the controller heard someone instruct, "'Nobody do anything stupid"' and no one would get hurt, the employee said. The controller heard no more conversations, The Telegraph reported. FAA controllers notified concerned government organizations, such as the military, the employee said. Controllers also shut down all other air traffic quickly to get other planes away from the rogue aircraft, the employee said. The Nashua controllers have learned through discussions with other controllers that an F-16 fighter stayed in hot pursuit of another hijacked commercial airliner until it crashed in Pennsylvania, the employee said. Although controllers don't have complete details of the Air Force's chase of the Boeing 757, they have learned the F-16 made 360-degree turns to remain close to the commercial jet, the employee said. "He must've seen the whole thing," the employee said of the F-16 pilot's view of United Flight 93's crash near Pittsburgh. The flight took off from Newark Airport for San Francisco, and authorities say the hijackers were headed for another target in Washington, D.C. The employee said the controller spoke with United Airlines Flight 175 for quite some time after terrorists took command of American Airlines Flight 11, the employee said. Many controllers also watched events unfold on the Nashua control center's television, but never expected Flight 175 to hit the second World Trade Center tower because of that sustained contact with the crew, the employee said. "After the first plane hit, nobody imagined it would happen again," the employee said. "We all thought that was it. It totally caught everybody off guard. "It's not in anyone's mind they're hitting a target," the employee said. "When somebody takes a plane over, they try to negotiate a release with money." One air traffic controller with the help of an assistant monitored the two Boeing 767s that toppled the World Trade Center, the employee said. The same controller handled Egypt Air Flight 990 when it crashed off the coast of Massachusetts in 1999, the employee said. The controller is "pretty disturbed" that he lost both planes, the employee said. The morning's surreal moments included a controller who arrived for work and discovered his wife was on the American Airlines flight, the employee said.