Prosecutors said Monday they indicted two South Koreans on charges of smuggling methamphetamine worth more than 4 billion won into the country from Cambodia.

The Daejeon District Prosecutors' Office said a 56-year-old, believed to be case's mastermind and whose identity was withheld, is suspected of smuggling in 1.3 kilograms of meth from the Southeast Asian country through Incheon International Airport, South Korea's main gateway, in September last year.

The amount is estimated to be enough for 43,000 people, according to prosecutors.

The suspect was arrested in Cambodia through a joint investigation in January and was extradited to South Korea last month.

Prosecutors arrested the other suspect, aged 47, last year while he was attempting to sell the meth at a motel in the country's central city of Daejeon. Prosecutors said they confiscated the 1.3 kilograms of meth at the site.

"Recently, the place of purchase has been diversified from China and the Philippines to Cambodia and Thailand," said an official, underlining the importance of joint investigations among the countries. (Yonhap)