Action News has confirmed Republic Airlines flight attendant Jaclyn Luby was carrying a .38 caliber Smith & Wesson revolver in her carry-on bag.
She was making her way through security in Terminal C around 6:30 a.m. Sunday to work a flight to Denver when TSA spotted the weapon in the X-ray machine.
"Why would a flight attendant bring a gun, why would she carry a gun, I don't know," US Airways passenger Devrim Eren said.
Republic Airlines operates flights for US Airways which told Action News Luby was immediately taken into another room.
A Philadelphia police officer was trying to unload the .38 when it accidentally fired a round into the wall.
Investigators say Luby said she forgot the gun was in her bag.
"You would expect she would be more vigilant about the fact she travels so much that it should be second nature to her to basically check it out and check her bags out before coming to the airport," traveler Brian Saldanha said.
Investigators say Luby, who is from West Goshen Township, Chester County, had a valid concealed weapons permit.
She was charged with a summary offense of disorderly conduct and released.
We've learned Luby has been a flight attendant for Republic Airlines for more than five years.
"We are human and everybody does make mistakes and I understand that even though she's a seasoned veteran she needs to be careful and I'm sure it will be a great learning opportunity for her," US Airways passenger Andrea Burger said.
Republic Airlines couldn't be reached for comment.
No one was injured when the gun went off, but Philadelphia police will launch an internal affairs investigation over the handling of that gun by their officer.