The police have booked a number of third-generation scions of South Korean family-owned conglomerates on suspicions they bought and used illegal substances even as the investigation into more drug dealers and buyers widens.

A grandson of SK Group founder Chey Jong-gun was apprehended Monday for allegedly buying liquid marijuana, the police said Monday. He is suspected of buying the drug, which is illegal in Korea, on 15 occasions and smoking it between March and May last year. 

He tested positive for marijuana use and has admitted to the charges. The police said they will seek an arrest warrant for him.

Chey received liquid marijuana via a parcel service after contacting a seller using the encrypted mobile messaging app Telegram, according to the police.

A grandson of Hyundai Group founder Chung Ju-yung was also booked on suspicions of purchasing marijuana between March and May last year. Chung, who is now staying abroad, is set to be called in for questioning.

The suspected purchases of marijuana came to light after a man, only identified by his surname Lee and said come from a wealthy family, was apprehended for smoking marijuana in February. He too has admitted to the charges, according to local media reports.

Lee is said to have told the police during the probe that he purchased marijuana for Chey and Chung, according to news reports.

The Seoul Metropolitan Police Agency also announced that they have launched an internal investigation into allegations that some officers conducted a slipshod investigation into Hwang Ha-na, a granddaughter of Namyang Dairy founder Hong Doo-young.

Hwang was booked in 2015 on suspicions that she gave methamphetamine to a person identified by the surname Cho and took the drug together. Cho was found to have later wired 300,000 won to a drug dealer’s bank account, which was given by Hwang. The police referred the case to the prosecution in 2017, with a recommendation not to file charges.

Hwang was never questioned by police and avoided indictment while Cho was sentenced to 2 1/2 years in jail suspended for three years, which triggered suspicions that the police helped Hwang avoid punishment due to her family background.

In its verdict, the court said that Cho “conspired” with Hwang to take methamphetamine on three occasions. It said they used the illegal substance together in 2015 and Hwang sold it to Cho.

Hwang was also charged with smoking marijuana in 2009. But her indictment was suspended in 2011 and she avoided any punishment, according to news reports.

Meanwhile, Hwang is currently under investigation for new allegations of drug use.

Namyang Dairy said Tuesday that the company has nothing to do with the allegations surrounding Hwang.

“Hwang has nothing to do with the management of the company. She and her family members neither retain a stake (in the company) nor do any related work for us,” the firm said in a statement.

By Ock Hyun-ju (laeticia.ock@heraldcorp.com)