DENVER (CBS4/AP)– More letters will be mailed to medical marijuana dispensaries located near schools.

On Thursday, U.S. Attorney John Walsh said 23 dispensaries within 1,000 feet of schools have until Feb. 27 to shut down or face federal penalties, which can include asset seizure or forfeiture of property. The warning letters dated Thursday were being sent to dispensary owners and their landlords.

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He said the letters were a first step and prosecutors were looking for medical marijuana businesses to target near schools. Walsh’s office declined to release a list of targeted businesses, saying they do not make public individuals under investigation.

State regulations prohibit medical marijuana businesses within 1,000 feet of schools but grandfathered in those businesses already in existence before regulations were passed last year.

“We’re going to move locations. I am not exactly sure yet, but we will open a new location in Denver that is obviously not within 1,000 feet of a school,” said Bio Care manager Samantha Beckmann.

After the initial mailing to 23 medical marijuana dispensaries, more letters soon will be sent out.

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“They can destroy these businesses with a two-page letter that took them 10 minutes to draft, but we won’t go that easily,” said Attorney Rob Corry.

Corry said there are far more than just 23 medical marijuana dispensaries located near schools.

“I still have worries but in fairness of the law, that moving them away from the school so that it’s not in sight of the school is going to be vital for the security of our children,” said Bromwell Elementary Principal Jody Cohn.

“I feel if you’re using state regulations right, I don’t think the federal government should come in and take that away from you,” said Beckmann.

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