ALBUQUERQUE, N.M. (AP) – A methamphetamine investigation on the Mescalero Apache reservation in New Mexico has resulted in federal charges against 18 suspected drug dealers and dismantled three drug trafficking networks in the region near the U.S.-Mexico border, federal officials said Monday.

U.S. Attorney Damon Martinez announced the results of the probe, saying from Las Cruces that Drug Enforcement Administration and Bureau of Indian Affairs agents led the investigation into meth trafficking after a rise in violent crimes on the reservation.

Those crimes included the February 2014 brutal assault of a 13-year-old girl whose attackers were believed to be high on meth, said Will Glaspy, the DEA special agent in charge for El Paso, Texas.

“Many of our young people are being poisoned by methamphetamine, and lives are being shattered by senseless drug-related injuries and deaths,” said Danny Breuninger, the Mescalero tribal president.

In addition to the 18 defendants facing federal charges, another 16 face prosecution in tribal court on drug-related charges brought as a result of the probe.

While agents have determined the methamphetamine was manufactured off the reservation and believe it was smuggled into New Mexico, investigators haven’t yet determined the source of the drug supply, Glaspy said.

The Mescalero Apache Reservation is about 100 miles north of the U.S.-Mexico border. Authorities said their investigation stretched into other parts of southern New Mexico, with agents investigating and arresting residents from Hobbs, Alamogordo, Socorro and other towns in the region.

Five of the 18 suspects facing federal charges were members of the Mescalero Apache Tribe.

Martinez said up to 40 percent of violent crime on reservations is meth-related.

In the past year, several tribes in other states – such as the Blackfeet in Montana and the Cheyenne River Sioux in South Dakota – have adopted resolutions to banish suspected drug dealers from their reservations as a way to confront the meth trade, with tribal leaders saying some cases have gone unprosecuted.

Federal codes indicate tribal courts can prosecute only misdemeanors, which include drug possession. Drug trafficking, a felony, is prosecuted in federal courts.

While applauding the investigation, Breuninger, the Mescalero tribal president, called on federal authorities to support more cross-agency investigations aimed at taking down drug trafficking networks in Indian Country.

“One of our greatest struggles today is maintaining our cultures, and anytime we have any individual coming on to the reservation trying to destroy that, that in my mind is disgusting,” Breuninger said.