DENVER (CBS4) – Denver police are cracking down on so-called marijuana tourism companies.

Police cited 31 people who were part of a bus tour which takes people between pot dispensaries on Friday.

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(credit: Andrew Caballero-Reynolds/AFP/Getty Images)

The tickets issued were for using marijuana in public, while a bus driver was arrested for suspicion of driving under the influence of drugs.

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A Denverite report states undercover officers joined the tour before arresting anyone.

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The tour companies say their services are legal, and their customers are permitted to use marijuana on the tour buses under Colorado law.