CHICAGO (NewsNation Now) — A new documentary is highlighting the often-ignored cases of missing and murdered Indigenous women and girls in Montana.

“Murdered And Missing In Montana” is a 90-minute documentary that focuses on the disappearance and deaths of three Indigenous girls.

Loni Coombs, host of the documentary, said the crisis of Indigenous women disappearing has been overlooked for a number of reasons.

“The history is systemic racism, discrimination and sexism. It started out where the young girls were used as property to barter. And that attitude that they’re invisible, they’re not worthy of being protected or looked after has carried on through the years,” Coombs said.

She also believes law enforcement in rural communities struggles with a lack of resources to investigate cases.

“In these cases, you have tribal lands, and there are tribal police that are supposed to govern those lands. But you also have local police, state police and federal police. There’s this issue with tribal police not being able to arrest non-Native Americans who come on to the tribal lands and commit crimes,” Coombs said.

According to the Centers for Disease Control and Prevention, Indigenous women and girls are murdered at 10 times the rate of any other ethnicity. They are twice as likely to be sexually assaulted. Murder is the third leading cause of death.

The documentary focuses on three girls who were ages 14-18 at the time of their deaths. They were living in Bighorn County, Montana. They went with their friends to a party before they vanished. Their bodies were eventually found near the location where they were last seen. Their families said their deaths have never been fully explained.

“Murdered And Missing In Montana” airs Friday at 8/7c on Oxygen.