ROSEVILLE (WWJ) – A crackdown on suburbanites who visit the city of Detroit to buy heroin has been dubbed “Operation Smack Down.”

In a two-day sweep, said Roseville Police Chief James Berlin, 155 people were arrested in connection with heroin-related crimes.

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Berlin said a majority of those in custody are Macomb County residents who would travel to Detroit’s east side to “meet their suppliers” — sometimes using public transportation.

“Users started to use the SMART Bus system as a way to avoid detection, using the Gratiot and Van Dyke corridors to get to Detroit to purchase their drugs,” Berlin explained.

Heroin use in metro Detroit, the chief said, has skyrocketed in recent years.

“A lot of people are scratching their heads: Why has heroin reared its ugly head again? There hasn’t been numbers like this since the 1960s; who knows why,” Berlin said. “And the amount of young people who are being drawn to this drug is the unbelievable.”

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Operation Smack Down was a multi-jurisdictional task force effort between multiple police department in Macomb County, and well as state police, prosecutors and federal authorities.

In a media release, Detroit Police Chief James Craig said — what he called an “unprecedented initiative” to combat heroin usage and trafficking in Macomb County and on Detroit’s east side —”utilized approximately 150 law enforcement officers from virtually every facet of law enforcement in a coordinated effort to curb the escalation of the local heroin trade.”

Berlin said, of those arrested on simple possession and usage charges, those who qualify will go into a drug treatment program

He stressed that heroin is not just a “Detroit problem.”

“The sources are everywhere. They’re in the suburbs, they’re out here,” he said. “Obviously, like any good business you go where your customers are. Unfortunately there’s a ready supply of customers here (in Roseville).”

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Police said some of those arrested were arraigned on Thursday and arraignments would continue Friday. The names of those in custody were not immediately released.