After family members of several Native Americans with mental illness asked authorities for help, their relatives were killed by law enforcement. The scenario has played out in Custer County and elsewhere in western Oklahoma at least three times in recent years. This is the third in a three-part series exploring the case of Mah-hi-vist Goodblanket, an 18-year-old member of the Cheyenne and Arapaho Tribes, shot by sheriff's deputies after his father called 911. See also parts one and two .

The Black Kettle National Grassland is a vast expanse of red earth topped with wind-whipped prairie grasses in western Oklahoma. A walking path there features an audio tour, in which a computerized voice calmly details how the U.S. Cavalry, led by Gen. George Armstrong Custer, surprised and then slaughtered a peaceful band of sleeping Cheyenne on November night in 1868, killing men, women and children.

He then took prisoners and ordered the gruesome slaughter of 875 of the horses at the encampment near the Washita River and the present-day city of Cheyenne.

Today, 60 miles east in Custer County — named for the officer — the battles fought in the local Native American community are still fierce and deadly. Poverty, mental illness and drug and alcohol abuse are huge problems in Oklahoma, home to 39 federally recognized tribes.

“The alcoholism and drug addiction rates are staggering in the Native American population. It’s staggering,” said Rosemary Stephens, the editor and chief of The Cheyenne and Arapaho Tribune, based at tribal headquarters in tiny Concho, west of Oklahoma City.

Cheyenne and Arapaho tribal lands are scattered throughout Custer County and elsewhere in western Oklahoma.

The killing of two Native Americans by law enforcement has fed racial tension in the majority-white law enforcement forces and minority Native population, she said.

“Custer County,” said Stephens, “is our Ferguson.”

In Custer County, law officers killed two mentally ill Native Americans in separate incidents in 2012 and 2013. Unlike with the shooting of unarmed black teenager Michael Brown in August 2014, in Ferguson, Missouri, marches, commentary and a cohesive call for change hasn’t followed the deadly force incidents in rural America.

Benjamin Whiteshield was in the midst of a paranoid episode on June 27, 2012, and went to the Clinton Police Department for help. He held a wrench to protect himself; he thought he was being followed. A Clinton officer fired a shot, striking him in the mouth and killing him.

Mah-hi-vist Goodblanket’s father, Wilbur Goodblanket, called 911 on Dec. 21, 2013, after his son started thrashing around the home and breaking windows. Mah-hi-vist Goodblanket, 18, had oppositional defiant disorder, a behavioral disorder marked by angry outbursts, trouble controlling temper and other symptoms. He was in the midst of a mental episode when Custer County sheriff’s deputies shot him. The department maintained that he was armed and throwing knives.