DENVER (CBS4) – A group of people accused of bringing over 45,000 pounds of marijuana into the Denver area each year has been indicted by a Jefferson County grand jury.

The grand jury returned a 96-count indictment against 23 people suspected of being involved in a major drug trafficking ring.

Police said the marijuana has a street value of $36 million.

The West Metro Drug Task Force, assisted by agents of the Drug Enforcement Administration started the investigation in May, 2010.

“They found that large tour buses were being used to transport thousands of pounds of marijuana from Mexico to a warehouse in Commerce City. The marijuana had been compressed into ‘brick’ form and was hidden in specialized compartments which had been installed underneath the buses,” Pam Russell with the Jefferson County District Attorney’s Office said in a statement.

Russell said the buses traveled twice a week from Mexico to the warehouse in Commerce City, carrying over 400 pounds of marijuana each time.

Police recovered 14 vehicles, seven firearms, 1,172 pounds of marijuana, 2 kilograms of cocaine, and 53 grams of methamphetamine.

Conrado Arellano-Casas, 32, is alleged to be the ringleader of the Colorado branch of the operation.

“A search warrant executed at his Arvada home led detectives to a loaded AK-47, other firearms and over $30,000 in cash,” Russell said.

Connie McKee leases the warehouse in Commerce City and says Arellano-Casas rented part of the space telling her it was for his roofing business, Arellano Construction.

“(He) moved in some roofing equipment, a trailer and a few jacks and shingles and things for his company,” she said.

Jose Jimenez-Chacon, 30, from El Paso, Texas, is believed to be the ringleader of the U.S. operation.

“This was a big drug trafficking organization located in Durango, Mexico. The real king pings of this operation don’t come across the border usually, they have others they work through,” Jefferson County District Attorney Scott Storey said.

Eighteen of the 23 men have been arrested. The remaining five are believed to be in Mexico.