Police have apprehended 90 Vietnamese nationals on suspicion of distributing and using drugs smuggled into the nation from Vietnam. 

The Busan Metropolitan Police said Wednesday that they apprehended the suspects and arrested 18 of them at six clubs in Sejong, Cheonan, Asan, Jincheon and Daegu after cracking down on bars and clubs across the nation between September and December of last year. 

Police suspect that seven of the apprehended individuals smuggled synthetic marijuana and ketamine worth more than one billion won, or nearly 692-thousand U.S. dollars, into the country from Vietnam in May. 

The number of people who were apprehended on suspicion of using drugs stood at 66. 

In the crackdown, police say they confiscated 300 million won worth of drugs, including one-and-a-half kilograms of synthetic marijuana and 139 tablets of ecstasy.

They also say 33 of the apprehended individuals have been deported for immigration violations.

Police put out an all-points bulletin for a Vietnamese man in his 20s they suspect of dealing drugs and are tracking him down together with Interpol.