Bui Van Lam, 32, was arrested for illegally trading drugs, the police of Hai Duong said Friday.
Authorities said Lam manages over 20 workers who come from mountainous regions in the north to Hai Duong to work at construction sites at industrial parks, for VND300,000 (US$12.20) a day.
As half of the workers were deemed drug addicts, Lam said he would give them drugs at VND100,000 per packet, and this money would be subtracted from their salaries at the end of each month.
A search at an apartment room in Nam Sach District, rented by Lam, revealed 12 paper packets and a plastic bag containing around 2.2 grams of drugs.