Hanoi police issued on Tuesday a warrant for the arrest of a karaoke bar owner who now stands accused of using his business as a front for narcotic sales.
By the time the warrant was issued, they said, Nguyen Trong Dai, 29, had fled the city.
Last Sunday, police stormed into the five-storey bar located at 145 Yen Phu Street and arrested 36 customers who were found to be in possession of illegal narcotics.
Police say they discovered 65 ecstasy tablets and 10 plastic packs of powdered ketamine from their pockets and on the floor.
A quick test showed 23 customers were positive with drugs.
A subsequent search of the house turned up another ketamine pack, two ecstasy tablets and assorted drug paraphenalia.
According to the police, Dai allegedly conspired with a drug addict to trade several kinds of narcotics in his bar.
Dai, the director of a construction company, hired a man to manage his bar to cover up his crimes, the police said.