GRAND JUNCTION, Colo. (KKCO) - Now that a ban on medical marijuana dispensaries has officially taken effect, the City of Grand Junction says any remaining businesses had to shut down their operations by the end of Thursday.

City Attorney John Shaver wrote a letter to dispensary owners that was distributed to them, explaining how the city will implement the ban.

He says the businesses must surrender their sales tax licenses immediately and are responsible for figuring out what to do with any remaining plants or products they have.

"It's really not up to the city to deal with that at this point," said Shaver. "Certainly, if they need a few days to try to wind up their business and do a few things we'll allow them that. But generally speaking, we're going to expect them to comply and make sure their businesses are ended."

If any dispensary owners are caught violating the ordinance they could be fined up to $1,000 per day and spend up to a year in jail.