WIND RIVER RESERVATION, Wyo. — Natasha Washakie has lived in the depths of addiction to methamphetamine and come back up.

She's seen friends trade sex for meth. She's seen one get her own children hooked on the drug, which among its side effects suppresses the appetite.

"We used to joke that she kept her whole family high so she wouldn't have to feed them," said the 28-year-old Northern Arapaho woman, who has been clean for 15 months after a 3-year addiction.

Washakie knows the drug, almost unheard of here before 2000, is slowly destroying this central Wyoming reservation.

She also knows where it comes from: a Mexican drug gang that arrived here more than four years ago hoping to shift the alcohol addiction of many tribal members to meth.

"Honestly, I think that was the best business decision they ever made," Washakie said sadly.

Authorities could hardly argue.

According to information gathered during an investigation that has so far led to more than 17 arrests, that gang is the Sinaloan Cowboys, an organization with a sophisticated structure and a Fortune 500 business plan — when you're a drug cartel looking to expand, go where the addicts are.

Continuing epidemic

Over a period of more than four years, the gang funneled nearly 100 pounds of meth with a value of more than $6.5 million into and around the reservation.

At least three gang members were dispatched from a Utah-based cell to reservation towns. They rented houses and met girlfriends. Using American Indian women, they gained entree to the reservation and established a network of more than a dozen dealers, many of them Native American.

"They identified the reservation as an addict-rich environment, a population that for years had been addicted to alcohol," said Robert Murray, an assistant U.S. attorney in Cheyenne, Wyo. He said information on the gang's plan to infiltrate the reservation had been garnered from multiple sources.

In a matter of five years, tribal leaders say, meth went from a marginal drug to a virtual torrent on this 2.2 million-acre reservation.

"It's an epidemic, and I don't think we've reached the peak," said Mark Russler, executive director of Fremont Counseling Services, which treats addicts.

Russler said the number of meth addicts at two facilities in Lander and Riverton — the region's largest — jumped from 5 percent or 6 percent of clients in 1999 to more than 25 percent.

From 2003 to 2004 — a year tribal police saw the worst increase in meth use — criminal charges for drug possession on the Wind River Reservation increased 353 percent. During that period, assaults tripled, theft nearly doubled and child abuse increased by 85 percent.