Passengers wait in a long line in front of check-in counters at Incheon International Airport. (Yonhap)

A live bullet was discovered at Incheon International Airport, west of Seoul, on Thursday, just one week after two live rounds were found on a plane, delaying its departure from the country's primary airport.

Airport police said they received a report at 4:23 p.m. that a live bullet was found in the departure hall on the third floor of Passenger Terminal 1. It was discovered by a cleaner who was segregating waste, they said.

Authorities conducted a search of the area, but no additional bullets were found. The ammunition will be sent to the National Forensic Service for examination, police said.

Last Friday, two live bullets were discovered on a Manila-bound Korean Air Lines plane as it was about to take off from the airport, resulting in the evacuation of all 230 people aboard and a delay of nearly four hours. (Yonhap)