The case of a Chinese couple who broke through security at Incheon International Airport should ring alarm bells, and very loud.

The case, in which the two passed through at least four layers of airport security in 14 minutes, followed the ruckus generated by the breakdown of the airport’s luggage system earlier this month. Both certainly damaged the reputation of the airport, which has boasted numerous best airport awards.

But more than mere reputation is at stake when it comes to security. It could be a matter of life and death, and a small loophole can put the entire nation in danger. What would have happened if the two had been members of a terrorist organization like the Islamic State?

What happened after the couple, both 31 years old, arrived at Incheon on Wednesday evening -- from Beijing via Jeju and Narita -- is simply astounding. Upon their arrival, they requested a permit to participate in tour programs for transit passengers, which the authorities rejected.

Then early Thursday morning, they broke through -- you could say they just walked through -- the security systems at the passenger terminal. Undetected by anyone, they walked into the departure lounge from the duty-free shopping area and then through a closed immigration counter and security checkpoint. It took just 14 minutes before they stepped out into the lobby of the passenger terminal, from where they proceeded to a taxi stop. 

The case also exposed a serious problem with the management of transit passengers. The couple was to board a plane bound for Beijing on Thursday evening. It was not until almost 24 hours later when authorities were alerted about their disappearance. 

Immigration officials, who nabbed them in Cheonan, about 135 kilometers from the airport, said that the couple paid 120,000 yuan (about $18,000) to get assistance to illegally enter the country. Those who helped them could have done the same thing in the past.  

The Land and Transportation Ministry announced some measures to tighten security, especially in the areas through which the couple trespassed. This is hardly sufficient. 

One can imagine -- if Incheon Airport has such a lax security system – what the situation might be like at the much smaller, more remote airports and seaports across the country. A comprehensive examination should be made promptly.