DENVER -- Medical marijuana dispensaries sprouting across Denver has a city councilman pushing an ordinance to tax and regulate the booming industry.

City Councilman Charlie Brown said he was spurred to act after a church school and merchants complained about three new pot dispensaries springing up in a South Broadway neighborhood in the past month.

"The principal called me because he was concerned when he saw a (neon marijuana leaf) sign go up," Brown said of the soon-to-open Dr. Reefer. The Dr. Reefer storefront sits across the alley from the playground for Rocky Mountain SDA Academy.

"Its playground looks right down on this dispensary," Brown said. "It's unbelievable. It's out of hand. It's out of control. It's the Wild West -- and we've got to get a grip on it."

Amendment 20, approved by Colorado voters in 2000, allowed individuals to use medical marijuana with a doctor's recommendation. But the ballot measure gave no guidance on regulating the pot dispensaries.

So, no state and local agencies oversee the growing number of marijuana outlets -- or even tracks where they are.

But Weedmaps.com offers high-tech mapping to help medical marijuana users "find your bud."

Punch a Denver zipcode into the Weedmaps.com and 40 local dispensaries pop up. Six dispensaries are within a three-block radius of Rocky Mountain SDA Academy, according to Weedmaps.com. Two of the dispensaries offer "mobile delivery service."

The site also touts an iPhone application that allows people to find the nearest dispensary on a map.

"There's no regulation. They don't even have to apply for a business license, unless they sell paraphernalia," Brown said.

Like Brown, law enforcement officials fear criminal elements taking over the thriving businesses. Four men were arrested last summer for robbing two 20-gallon tubs of pot from a Boulder dispensary.

The councilman wants to regulate dispensaries like bars and liquor stores, whose owners have to undergo FBI criminal background checks.

"That's what's missing. We don't know how many drug lords are in business in Colorado now. We know that they're coming from California and other states," Brown said. "This is a growth industry and that's no pun. You've got lawyers who are making gobs of money on this."

Colorado Attorney General John Suthers is urging state lawmakers to strengthen Colorado regulations of dispensaries after the Obama administration recently told federal authorities not to arrest or prosecute medical marijuana users and suppliers.

"Colorado has seen a rapid proliferation of medical marijuana dispensaries and patients since the Justice Department earlier this year announced it would not actively prosecute medical marijuana businesses -- despite the fact that marijuana remains an illegal drug under federal law," Suthers said in a statement Monday.

Suthers said the new federal policy deferring enforcement to the 14 states that allow medical pot "relies on the faulty assumption that Colorado has clearly defined laws on medical marijuana. In fact, it does not."

"Dispensaries and grow operations, for example, are not mentioned in either Colorado's Constitution or its statutes. This vacuum has given rise to problems I and other law enforcement leaders have highlighted over the past few months. This legal vacuum also has left Colorado's towns and cities to grapple with the state's burgeoning marijuana trade," Suthers said.

On Tuesday night Greeley joined several other cities, including Broomfield and Superior, that have banned dispensaries. Other cities have issued temporary moratoriums on new dispensaries, including Lafayette, Louisville, Longmont and Breckenridge.