An alarm sounded when a TSA officer staffing the checkpoint X-ray monitor spotted the weapon -- along with boxes of ammo -- on Monday, the Transportation Security Administration (TSA) said.
Port Authority police collected the bag and examined its contents.
Meanwhile, a TSA supervisor and lead officer followed the traveler, who grabbed his other belongings and tipped away toward his gate, the agency said.
They kept an eye on him -- making sure he didn't interact try to hand off or leave anything else -- until authority officers grabbed the man and returned him to the checkpoint.
A computer check found the gun had been reported stolen and the ex-con was arrested.
The TSA didn't identify him.
Law enforcement sources confirmed, however, that Desmond L. Herring, 38, of Atlanta was booked into the Essex County Correctional Facility following the arrest.
Herring, who records show has a drug-related criminal history in New York State, is charged with multiple weapons offenses -- including being a convicted felon in possession of a firearm -- and possession of stolen property.
“This individual knew he had a loaded gun with him and realized that he would be questioned by police, so he tried to distance himself from the carry-on bag and its contents by walking away,” said Thomas Carter, the agency's federal security director for New Jersey.
“This was a very good catch on the part of our TSA officers," Carter said. "It turns out that the man has an extensive criminal record and the gun was reported as having been stolen.
"Not only did TSA prevent a deadly weapon from getting on board an aircraft, but we aided law enforcement in getting a dangerous individual off of the street.”
The incident came a few days after TSA agents grabbed a Florida man as he tried to board a plane at Newark Airport with a gun and a box of ammo in his carry-on baggage.
SEE: Traveler Caught With Gun At Newark Airport Checkpoint
That makes 14 gun arrests at Newark Liberty International so far this year.
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