(Bloomberg) -- New York City is escalating its crackdown on illegal marijuana stores, seeking to force landlords to evict the unlicensed shops that have proliferated across the city as state-sanctioned weed retailers begin operating.

Manhattan District Attorney Alvin Bragg said Tuesday that he was putting the property owners of 400 unlicensed smoke shops on notice: Evict any tenants that are selling illegal cannabis — or the state will do it for you.

“We have given them plenty of time to clean up their act,” Mayor Eric Adams said at an Upper West Side press conference Tuesday with Bragg and other elected officials. “We want people to know that you can’t just open a shop.” 

Also on Tuesday, the city filed nuisance-abatement lawsuits against four stores that it says sold cannabis products to underage police informants — all a short distance from the two legal stores  in Greenwich Village that have opened so far. 

The latest actions represent a new phase in the city’s efforts to shut down an estimated 1,400 illegal cannabis stores. 

The proliferation of illicit operators poses a threat to New York state’s 2021 marijuana law, which seeks to license — and tax — adult-use cannabis dispensaries. Preferences for licenses will go to people who have been impacted by past marijuana enforcement.

A city-state task force has been conducting raids and investigations of the shops and has issued 566 civil citations and seized $4.1 million worth of illegal products.  

Despite the task force’s work, the smoke shops have remained a problem for law enforcement and legislators who say that the stores are undeterred by raids. 

Read more: NYC’s first legal pot shop aims for $1 million in revenue

City Council Member Gale Brewer, who represents the Upper West Side, said interns from her office counted 61 illegal shops from West 54th Street to West 108th Street last year. That’s up from only six or seven the year before, she said. One store raided by the New York City sheriff reopened the next day.

Lawmakers and cannabis attorneys have said that targeting building owners would be a more effective approach to eliminating the smoke shops, which have proliferated since the state legalized recreational adult-use marijuana without implementing a legal retail market soon after. 

So the city is bringing a back a page from its anti-drug efforts from the 1970s and ’80s, said Manhattan Borough President Mark Levine. “Unlicensed stores are making so much money that fines are a cost of doing business,” he said. “This strategy of taking their leases, that’s a whole other level.”

Advocates for the legal weed stores say there’s an urgency to shut down the illegal stores, but that the city should use civil remedies rather than criminal ones.

“Cannabis attorneys here in NYC have been saying for a while now that this was the action that needed to be taken,” cannabis attorney Jeffrey Hoffman said via email. “We want no arrests, no convictions and no incarcerations. The appropriate action is to get the landlords to address the issue.” 

(Updates with additional details beginning in fourth paragraph. A previous version of this story corrected the value of illegal products seized.)

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