FBI spokesman J.J. Klaver tells the Associated Press that US Airways Flight 1070 has been cleared by authorities who swept the jetliner looking for explosives. He says the situation doesn't appear to have any connection to terrorism.
However, the search continues for a mysterious man dressed as an employee who was seen loading the plane.
It all began shortly before 11:00 a.m. when two US Airways employees were loading the flight bound for Bermuda.
A third man helped the two employees and, police say, he was in a US Airways uniform. However, the man did not have any identification.
The man then walked away and could not be found.
Those two employees then alerted authorities, who stopped the plane.
The Airbus 319, with 102 passengers and five crew members on board, was then turned around on the runway and moved to a remote location, surrounded by emergency vehicles with lights flashing. It was then unloaded for investigation.
Passengers were safely let off the packed plane and put on waiting buses.
A passenger on the plane, Amanda Benner, said she and others on board were told "there was a TSA security breach" and were asked to exit the plane through the Jetway and back into the terminal.
"We're in the airport now. They took us off," she told The Associated Press by cell phone. "They told us there was a TSA security breach and we've had to leave everything on the plane and get off. They're re-screening everything on the plane."
Benner and her husband were en route to Bermuda for a long weekend for their 15th wedding anniversary.
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The Associated Press contributed to this report.