Evidence seized in a drug scam case targeting teenage students, in this April 27, 2023 photo. Yonhap

The Supreme Court finalized heavy prison terms, ranging from seven to 18 years, for four men connected to a high-profile drug scam case where young students were deceived into consuming drug-laced drinks, judicial officials said Friday.

In the ruling made last month, one of the four defendants, a man surnamed Gil, 27, was given an 18-year prison term for producing beverages spiked with 10 grams of meth and distributing them to random teenagers.

The top court also sentenced two of them, surnamed Park and Kim, to 10 years in prison, as well as a phishing scammer, who contacted the parents of the students and tried to extort money from them, to seven years behind bars.

The drug scam shocked South Korean society, in which drug-laced beverages were handed out to teenage students in Seoul's southern Gangnam Ward with false labels in April last year, claiming they were intended to enhance memory and concentration.

Investigators found that Gil had hired four part-time workers to host a "tasting event" for drinks designed to boost concentration levels in the district crammed with academies and handed out the drug-spiked drinks to 13 students.

Nine of those who received the beverages drank them, and six suffered symptoms, such as hallucinations.

The ring reportedly committed the crime to blackmail the parents of students who drank the beverages, saying they would report their children to police for drug charges, but failed to extort money from them after the parents notified police.

Meanwhile, the mastermind of the case, who gave orders from China, was sentenced to 23 years in prison by the district court in July. He has filed for appeal. (Yonhap)