Transportation Security Administration personnel stopped a 36-year-old woman going through a security checkpoint with a handgun and ammunition Thursday at Daniel K. Inouye International Airport.

TSA spokesman Mark Howell said the woman arrived at a checkpoint with an unloaded Glock 17 9mm with an ammunition clip in a carry-on bag.

Airport Sheriffs Dispatch received a call from TSA at 7:04 a.m. for sheriffs to respond to a checkpoint after X-ray screening indicated a possible firearm and live ammunition in a carry-on bag.

Deputy sheriffs arrested the woman on suspicion of firearm and ammunition violations and having an unregistered firearm, Department of Public Safety spokeswoman Toni Schwartz said in an email.

She was released pending investigation by the Attorney General’s Office.

Howell said that whenever an X-ray operator finds a firearm, he or she stops the lane and escorts the passenger to another area where law enforcement decides to cite or arrest.

TSA may issue a civil penalty up to $13,333.

Howell said 99.9 percent of the time, passengers’ excuse is: “Oops, I forgot to take it out of my bag. The real takeaway from this is take five minutes of time and check what’s in your bag.”

Unloaded firearms are permitted in checked luggage, but must be properly packed and locked in a padded, hard-sided case. Ammunition, boxed or in a magazine, is also allowed. Go to TSA.gov for details.

In Honolulu, TSA found three firearms in carry-on bags in 2018, compared with 298 in Atlanta, the U.S. airport with the highest number of firearms confiscated.

TSA typically sees high numbers of firearms in open-carry states such as Georgia and Texas, Howell said. A total of 4,239 were found nationwide in 2018.

Even in busy airports in states that prohibit open-carry, numbers are much lower. Los Angeles International Airport had 57 and La Guardia Airport and Kennedy International Airport both had two each.