Gov. John Hickenlooper on Monday called the marijuana gray market in Colorado a “clear and present danger” that demands tougher regulations and enforcement.

Reacting to recent busts, Hickenlooper said the state must “move swiftly and aggressively to make sure the illegal activity is stamped out.”

“If we don’t stamp it out right now, it becomes acceptable. And then, all of a sudden, people are going to start getting hurt,” the Democrat said in an interview. “If you let crime grow, it will breed on its opportunity.”

The concern about Colorado-grown marijuana being sold illegally in other states is increasing after a recent crackdown by local and federal law enforcement that led to indictments from the U.S. attorney’s office.

In March, a DEA Drug Task Force raided five homes in Pueblo West and seized 1,879 marijuana plants, 16 pounds of processed marijuana and nine handguns and shotguns, according to court records. Seven men were indicted in U.S. District court on 13 counts of illegal marijuana production and distribution.

“I take this very seriously,” Hickenlooper said. “This is one of the things we worried about in the very beginning. But when we see the evidence, we better respond.”

The governor’s remarks came after he asked state lawmakers to set aside $16 million in marijuana tax revenues for new initiatives related to controlling the gray market as part of his $28.5 billion state budget proposal.

The extra dollars would cover the cost of law enforcement investigations and prosecutions. The administration also is considering legislation to tighten regulations on who can grow marijuana at home and the number of plants allowed.

The illegal trade is operating as part of the gray market, in which marijuana is grown legally but sold illegally. The state’s medicinal marijuana law allows patients and caregivers to grow up to 99 plants in a residential setting, while the state’s recreational marijuana law allows growers to form vast cooperatives cultivating six plants per individual.

Rachel Gillette, the acting interim executive director at Colorado Norml, a marijuana advocacy organization, said growers need to operate within the bounds of the law, and she is worried additional state regulations will go too far.

“The bottom line is you can write a bazillion laws, but if people are willing to break them … it doesn’t necessarily help,” she said. “The part of the reason this gray market even exists is because the federal government refuses to acknowledge the medical efficacy of marijuana, as well as continues to follow archaic law pertaining to a drug war that has clearly failed.”