FARGO, N.D. (AP) -- Federal authorities unsealed indictments Monday against 22 people charged with conspiracy to sell heroin and other drugs on an Indian reservation in the heart of the North Dakota oil patch.
The first indictment in the investigation, dubbed "Operation Winter's End," was filed in March, but authorities didn't make the case public until Monday because of the ongoing investigation.
Investigators say heroin and other drugs were brought to the Fort Berthold Indian Reservation, located southeast of Williston within the Bakken oil patch, from other parts of the country.
"This multi-jurisdictional investigation has struck a blow against a large national drug trafficking organization, which has plagued the good people of North Dakota," said Chris Warrener, special agent in charge of the FBI's Minneapolis office.
The case, USA v. Lopez, charges three out-of-state residents, brothers Horatio "Happy" Lopez, 33, and Oscar Lopez, 27, of Wasco, Calif., and Michael Jason Smith, 32, of Evergreen, Colo. The other defendants are from North Dakota.
The indictment also charges the defendants with conspiracy to distribute methamphetamine. They face maximum sentences of life in prison without parole.
"The charges filed as a result of Operation Winter's End are a first step to address the increased organized drug distribution activities on the Fort Berthold Reservation and in northwestern North Dakota," U.S. Attorney Timothy Purdon said in a statement. "This indictment will help make both reservation and non-reservation communities in the Bakken oil patch stronger and safer."
Smith was arrested in December after holding officers at bay for two days by barricading himself in a home in New Town. He was taken into custody on Dec. 20 when officials used a front-end loader to break into the home.
Law enforcement officials have said that organized crime and other illegal activity is increasing with the influx of people looking for work in the energy industry. Recent U.S. Census Bureau estimates show that Williston, in the far northwestern corner of the state, is the fastest-growing metropolitan area in the country.
Federal authorities have increased policing efforts in oil country by adding several FBI agents in Minot and Bismarck and a Bureau of Alcohol Tobacco and Firearms agent in Bismarck.
"The U.S. attorney's office is committed to an anti-organized crime strategy in the oil patch that is built on close cooperation between federal, state, local, and tribal law enforcement agencies," Purdon said.
Authorities have said heroin sales in North Dakota are on the increase after a decade of seeing only sporadic cases. Some investigators believe the abuse of prescription painkillers is fueling the market for heroin because it's a cheaper alternative and more readily available.