DENVER (KDVR) — A large-scale cocaine trafficking investigation in Adams County led to the grand jury indictment of 31 people with charges involving organized crime, drug trafficking, money laundering and more, according to the 17th Judicial District Attorney’s Office.

The 18-month investigation, called Operation Full Circle, included the seizure of 14,600 grams of cocaine, four firearms, 15 vehicles, five residences and $283,514 in cash, according to a press release from the DA.

The drugs were allegedly brought to Adams County from Juarez, Mexico, through Martin Mena-Flores and his brother Gustavo Mena-Flores, as well as a number of their associates, according to the release.

The North Metro Task Force and the DEA say the alleged Mena-Flores criminal enterprise had avoided law enforcement while distributing cocaine in the area for 15 years.

“This partnership and the indictment should send one important signal to all who are dealing this poison in our community: we’re going to take you down,” District Attorney Brian Mason said.

The alleged criminal activity took place in Adams County, mostly in Brighton, according to court documents.

As of Monday, 18 of the suspects were taken into custody. Others who were indicted had yet to be arrested, and investigators believe they may be in Mexico.

Of the 31 people indicted, 16 are facing charges under the Colorado Organized Crime Control Act and the other 15 are facing charges concerning drug trafficking.