An Arizona woman died and a pilot was seriously injured in a Sunday morning plane crash southwest of Meeteetse.

Authorities identified the deceased as 78-year-old Mary Lou Sanderson of Lake Havasu, Arizona, while the unidentified pilot was flown to a Billings hospital for medical treatment.

As for what caused the private, two-seat airplane to crash, that’s being left to an investigation by the National Transportation Safety Board. Personnel from the agency reportedly traveled to the site on Tuesday as part of their investigation.

The American Champion 8GCBC Scout crashed a little before 11 a.m. Sunday near Francs Peak, within the Shoshone National Forest. The incident was reported by a hunting party that heard the plane go down and then saw smoke rising from the area.

The hunters, Steve Atencio and J.R. Larsen, told Cowboy State Daily that they hustled to the scene and helped move the pilot away from a growing fire. They told the publication that the man suffered severe burns and indicated he’d broken his back.

Park County Search and Rescue personnel were flown into the site by a helicopter provided by Tip Top Search and Rescue of Sublette County. The Park County volunteers helped load the injured pilot into a separate medical helicopter operated by First Flight and also helped recover Sanderson’s body, said Monte McClain, spokesperson for the Park County Sheriff’s Office.

A few firefighting personnel with the Forest Service were also flown to the scene to contain the flames. They built a line around most of the so-called Reef Fire before hiking out for the night due to some incoming weather and concerns about grizzly bears, which “are always an issue up there,” said Evan Guzik, a spokesman for the Shoshone National Forest.

Roughly seven personnel returned the following day — reaching the scene through a combination of trucks, ATVs and hiking — and finished containing the fire, Guzik said. It burned about a 10th of an acre in total, he said, with crews continuing to monitor it.

As for the wreckage, Guzik said someone affiliated with the aircraft will “give their best effort to remove it” from Francs Peak, “and we’ll work with them to make that happen.”

The crash occurred almost exactly 11 years after a 17-year-old pilot became disoriented and crashed a Cessna 172 in the same general area. She suffered minor injuries and was helped to safety by two men who’d been scouting elk in the area.