When an apartment flower bed was dug up, a bundle of drugs wrapped in plastic was discovered.

["You just need to dig here. (There it is, there it is.)"]

Cannabis intended for sale through the so-called "dead-drop" method was uncovered.

The drugs were distributed by a man in his 30s, surnamed A, and another woman in his 30s, surnamed B.

Previously, in May of last year, ketamine, known as a club drug, was found under an airplane seat after a flight arrived at Incheon International Airport from Cambodia.

Through passenger and CCTV analysis, A was identified as a suspect, and an analysis of the mobile phone led investigators to the whereabouts of accomplice B and the cannabis.

B was emergency arrested when ketamine was found hidden inside underwear upon entering through Incheon International Airport from Cambodia on August 7.

On December 16 of last year, three packs of cannabis made into cigarette forms were found in the accessible restroom of the Incheon Airport arrivals hall.

Since there were no CCTVs inside the restroom and no fingerprints were detected, the investigation team analyzed the movement routes of visitors using CCTV footage recorded around the restroom entrance for two months.

A 30-year-old man, surnamed C, was caught wearing different clothes when entering and leaving the restroom, and a search of his vehicle revealed cannabis in the exact same form.

Through forensic analysis of mobile phones, the investigation team additionally booked two men in their 30s who smuggled in cannabis and chocolates containing hallucinogenic ingredients along with C.

Incheon Airport Customs stated, "Drug offenders are smuggling in narcotics using increasingly covert and sophisticated methods," adding, "We will completely block the introduction and distribution of narcotics into the country through airtight crackdowns."

(Reported by Kim Hyemin | Produced by Lee Seyoung | Video by Jeon Mingyu | Produced by SBS Digital News)