A doctor has been booked in a drug scandal involving actor Lee Sun-kyun and singer G-Dragon of K-pop group BigBang on suspicion of providing the illegal drugs.

According to the Incheon Metropolitan Police on Thursday, the doctor is under investigation for an alleged violation of the narcotics law by providing the drugs to Lee as well as the singer, whose real name is Kwon Ji-yong, and others for free through an entertainment venue in Seoul's Gangnam area.

A total of ten people in the scandal are now under police probe, including Lee on suspicion of using marijuana and other narcotics at the residence of an employee at the Gangnam establishment since early this year.

The employee, who has been taken into police custody on similar charges, is also accused of blackmailing Lee to pay 350 million won, or around 258-thousand U.S. dollars.

The police are soon expected to conduct hair and urine sample testing on Lee and Kwon.