The Transportation Security Administration said Wednesday that proper procedures weren't followed when a California police officer inadvertently left her handgun in a carry-on bag on a trip to Taiwan last week.
Taiwan's aviation police said Friday that a 43-year-old officer was questioned after turning in her gun on arrival in Taipei on a flight from Los Angeles.
"When she entered Taiwan, she realized she had a gun with her. She reported it to airport authorities," the Aviation Police Bureau said in statement, according to Reuters.
The TSA said the blame lay at one of its checkpoints.
"TSA has determined standard procedures were not followed and a police officer did in fact pass through the checkpoint with a firearm," it said in a statement. "TSA expects every employee to follow procedures and holds its workforce appropriately accountable."
The officer planned to travel to Bangkok in Thailand but was detained and questioned, Reuters reported.
TSA screeners found a record number of guns at U.S. airports in 2016 — 3,391 firearms — the agency said in its annual Year in Review report released in January. That number is an increase of 28 percent from the year before.
TSA rules prohibit guns from being stored in carry-on baggage, although travelers are allowed to transport them as checked luggage as long as the firearms are unloaded.
Rules about transporting guns in luggage received new scrutiny after a man allegedly checked a handgun case on a flight from Anchorage, Alaska, to Fort Lauderdale, Florida, in January, retrieved the bag and loaded the weapon in a restroom, and then opened fire, killing five people.
The alleged gunman, Esteban Santiago, had complained of hearing voices in the weeks before the shooting rampage. Santiago, 26, pleaded not guilty in January to 22 counts.