Transportation Security Administration screeners at a major U.S. airport missed finding a knife tucked inside a passenger's bag and may not have taken the proper precautions when handling a hazardous device, MyFoxNY.com reported.

TSA workers at New Jersey's Newark Liberty Airport failed to spot a knife inside a passenger's bag, law enforcement sources reportedly told the station. The passenger voluntarily turned it over to authorities minutes before boarding the flight, and was allowed to get on the plane without being interviewed, according to the station.

Law enforcement sources said that TSA screeners also may have improperly handled a smoke bomb -- the size of a dynamite stick -- that was reportedly found inside a passenger's bag on the same day. That passenger also was allowed to board the plane, MyFoxNY.com reported.

The TSA, however, has refuted part of the report, saying the device apprehended was not a bomb -- it was a firework -- and that its officers "did follow proper protocol for handling hazardous material."

Ann Davis, a spokeswoman for the TSA, told Foxnews.com that the person carrying the device was interviewed by Port Authority police and was not arrested.

She said that the individual carrying what she described as a "three-inch folding knife" was allowed on the plane only after being interviewed by officers.

"The TSA identified the officer responsible for missing the knife and she will be sent for remedial training," Davis said.

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