DENVER (AP) — Colorado is doing a good job keeping legal marijuana from spilling beyond state borders despite a newly unsealed indictment alleging 32 people earned millions of dollars by illegally exporting tons of the drug to other states, the state’s Attorney General Cynthia Coffman said Thursday.

The group falsely posed as licensed medical marijuana caregivers and small business owners and moved as much as 400 pounds of pot outside of Colorado, mostly to Minnesota, each month, according to the indictment.

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Couriers returned to Denver with hundreds of thousands of dollars at a time, making about $12 million over four years.

The group chose to operate in Colorado over other states, believing it could “hide in plain sight” inside the state’s commercial marijuana industry, the indictment says.

Authorities said one of those charged used planes from his skydiving business to make pot shipments. But most often, the group would simply load up a car and drive the pot from Denver to Minneapolis, where it was distributed and sold, the indictment says.

Coffman announced the indictment a day before her deadline to defend Colorado against a lawsuit by Nebraska and Oklahoma alleging the state’s legalization of marijuana has caused the drug to flow freely into other states.

She said the issues raised in the lawsuit and those in the indictment are different, and the latest pot bust shows authorities won’t tolerate those who exploit the state’s legal industry for criminal gain.

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But the case also shows a growing number of criminals are moving to Colorado to capitalize on the state’s “inadequate” marijuana regulations, said Kevin Merrill, assistant special agent in charge of the Denver office of the Drug Enforcement Administration.

In a policy statement last year, the U.S. Justice Department said it wouldn’t stand in the way of pot legalization in Colorado and other states, provided they abide by certain restrictions, including keeping pot from being trafficked into other states where it remains illegal.

Yet, authorities believed state court, rather than federal, would be the best place to prosecute the 32 indicted on charges including racketeering, felony cultivation and distribution of marijuana, money laundering and conspiracy, First Assistant U.S. Attorney Bob Troyer said. Investigators are looking at other cases involving out-of-state pot shipments, he said.

Coffman called upon legal pot businesses to help officials eliminate the black pot market, which has persisted since legalization.

“You, too, have a vested interest in stopping bad actors, like this group,” she said.

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