Authorities are conducting a manhunt at Mount Rainier National Park in Washington State after a park ranger died in a shooting Sunday following a routing traffic stop, authorities said.

Benjamin Colton Barnes, a 24-year-old believed to have military experience and survivalist skills, was a “strong person of interest” in the slaying of Margaret Anderson, authorities said, after recovering Barnes’ vehicle, which had weapons and body armor inside,

Authorities believed the gunman was still in the woods with an assault rifle. They asked people to stay away from the park, and for those already inside to leave, but Ed Troyer, a Pierce County Sheriff’s spokesman, said there were about 100 people hunkered down in lodges and cabins on the mountain. They were asked to stay put because they could be in the line of fire.