The American Bus Association (ABA) is praising the work of Federal and Local law enforcement officials in Colorado after authorities broke up what they say is a multi-million dollar marijuana ring, that allegedly was using motorcoach buses to smuggle the drugs from Mexico into the Denver area.

The Jefferson County Colorado District Attorney’s Office in Golden, Colo., says the smugglers used the motorcoaches to ship more than 45,000 pounds of pot into the Denver area during an 11-month period, beginning in May 2010. The Mexican drug cartel Los Zetas is suspected of being the marijuana source.

A 96 count indictment naming 23 suspects was returned by a Grand Jury on June 3rd. The indictments were announced July 11th by the District Attorney’s Office.

The District Attorney’s Office says the buses did not carry passengers, only a driver and a lookout.

“The American Bus Association is pleased law enforcement agencies in Colorado have stopped this drug ring from operating. We urge the Federal, State and Local officials to keep the pressure on,” said Peter Pantuso, CEO and President of the ABA.

Authorities say the marijuana was compressed into bricks and hidden in specialized compartments installed underneath the buses. It’s believed the buses started their trips in Durango, Mexico, entering the U.S. in El Paso, Texas and then were unloaded twice a week in Commerce City, Colorado at a warehouse.

Typically each bus carried 400 pounds of marijuana, authorities said.