(CNN) Across the Western US, Native American women are falling victim to violence in alarming numbers, officials say.

In 2018 alone, more than two dozen Native Americans -- the majority of them women -- went missing in sparsely populated Montana, according to US Senator Jon Tester.

"We're here today because we have an epidemic on our hands," Tester said during a Senate Indian Affairs Committee hearing last month. "Native Americans in Montana and across this country are dealing with violence at a much higher rate than the rest of the population ... you cannot set foot in Indian country without hearing a heartbreaking story about this growing problem.

"Twenty-four doesn't sound like a lot, but in a state of a million people if you (projected) that out through the (overall) population, that would be a ton of folks," he added. "We gotta find a solution to this."

Tester and another Senator from Montana, Steve Daines, say they will reintroduce a bill that would require the Department of Justice to overhaul law enforcement protocols and improve data collection regarding slain or missing Native Americans.