Airport border police on September 15 transferred the case and seized items to HCM City Police for further investigation.
The items were discovered on September 6 during baggage screening at Terminal 3. Police identified the 21-year-old passenger who was due to fly from HCM City to Thanh Hoa.
A search of the passenger's checked backpack uncovered nine items resembling ammunition and cartridge cases.
The passenger told police that the items had been found while extracting sand in Vinh Long Province in August and were being kept as collectibles.
A forensic examination by HCM City Police determined that five of the items were live military ammunition and remained usable, while the other four were spent cartridge cases.
Tan Son Nhat airport border police warned people against illegally transporting or possessing weapons, explosives or other dangerous items aboard aircraft. Anyone who finds such items should immediately report them to authorities to ensure aviation safety.