South Korea's national customs agency said Thursday it would combat drug trafficking activities, as international drug dealers can reach out to users via encrypted internet.

The total volume of drugs confiscated upon arrival came to 624 kilograms in 2022, which the authorities estimate to be equivalent to 8.9 million doses of methamphetamine, cannabis, Chinese pain relievers containing phenobarbital and illegal synthetic drugs combined.

Although the figure was halved from that of 2021, this is a worrying sign, as nearly all of the confiscated narcotics this year were bound for illegal trade in Korea, according to the customs agency.

Narcotics for Korea rose about 33 percent compared with 470 kg in 2021, according to the agency. In 2021, the remaining 800 kg were caught en route to other drug-consuming countries.

About 90 percent of drug trafficking attempts caught were for delivery to Korean drug users via either international mail or express courier parcel services over the past two years until 2022, in contrast with the level of some 50 percent in 2019 and 2020.

Behind the upsurge is the rise of encrypted internet as a tool to trade narcotics with the advent of the COVID-19 pandemic in what international drug crime rings see as a lucrative narcotic market, according to Yoon Tae-sik, commissioner of the Korea Customs Service.

"Korea is seeing a growth of narcotics smuggling for the purpose of consumption here, with international drug traders involved, as the products tend to be traded at a comparatively higher price than other countries," Yoon told reporters at a briefing held at Seoul Central Customs headquarters on Thursday.

Yoon said the authorities will set up new special teams to enhance its capabilities to seize drugs delivered via postal service at airports or sea ports, and to track down online narcotics trading with forensic tools.

In addition, customs authorities will triple the number of drug-related investigators, deploy more drug monitoring scanners and develop new systems to capture the small quantity of narcotics. The reward for reporting drug-related crimes will double to 300 million won ($245,300) in the first half.