The three largest U.S. drug distributors will pay more than $75 million to resolve claims they fueled an opioid epidemic in the Cherokee Nation’s territory in Oklahoma, marking the first settlement with a tribal government in the litigation over the U.S. addiction crisis.

Cherokee Nation Principal Chief Chuck Hoskin on Tuesday said the settlement, which will be paid over 6-1/2 years, would “enable us to increase our investments in mental health treatment facilities and other programs to help our people recover.”

The deal announced by the Cherokee Nation came after distributors McKesson Corp, AmerisourceBergen Corp and Cardinal Health Inc, along with the drugmaker Johnson & Johnson, agreed to pay up to $26 billion to resolve similar claims by states and local governments.

That settlement did not cover any of the country’s Native American tribes. The three distributors are in talks to resolve those cases, and other companies continue to face similar lawsuits.

Drugmakers Teva Pharmaceutical Industries Ltd and Endo International Plc on Tuesday separately said they agreed to pay $15 million and $7.5 million, respectively, to resolve claims they contributed to the opioid epidemic in Louisiana. Teva will also donate $3 million worth of medications.

The distributors in a statement called the deal “an important step toward reaching a broader settlement with all federally recognized Native American tribes across the country.” The companies deny wrongdoing.

The Cherokee Nation became the first Native American tribe to sue drug distributors and pharmacy operators in 2017. The sovereign Cherokee Nation has more than 390,000 citizens.

It accused the distributors of flooding its territory with millions of prescription opioid pills, an oversupply of addictive painkillers that resulted in abuse and overdose deaths that disproportionately affected Native Americans.

More than 3,300 similar lawsuits have been filed by states, counties, cities and tribal governments. Nearly 500,000 people died due to opioid overdoses in the United States from 1999 to 2019, according to the U.S. Centers for Disease Control and Prevention.

The Cherokee Nation, represented by the law firms Boies Schiller Flexner, Fields PLLC, and Whitten Burrage, also sued pharmacy operators CVS Health, Walgreens Boots Alliance Inc and Walmart Inc. They deny wrongdoing.