WIKIEUP, Ariz. (AP/CBS13) — Federal authorities on Sunday were at the scene of the crash of a small plane that killed two crew members, including a former Stockton fire chief, responding to a wildfire in northwestern Arizona.

Both people aboard the Beechcraft King Air C-90 aircraft died in Saturday’s crash.

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The state Bureau of Land Management on Sunday identified the victims as Air Tactical Group Supervisor Jeff Piechura, 62, a retired Tucson-area fire chief who was working for the Coronado National Forest, and Matthew Miller, 48, a pilot with Falcon Executive Aviation contracted by the U.S. Forest Service.

Piechura became the Northwest Fire District’s first chief in November 1988 and held that job for 24 years before retiring. He also worked with the Stockton Fire Department and left that role in 2015 and also spent some time with the Sedona Fire District in Arizona.

“Our hearts go out to the families of our brave wildland firefighters,” an Arizona Bureau of Land Management spokesperson said in a statement.

Bureau officials said the plane went down around noon Saturday as it was doing aerial reconnaissance and helping direct aviation resources over a lightning-caused wildfire burning outside Wikieup, a tiny Mohave County community about 123 miles (206 kilometers) northwest of Phoenix.

The wildfire ignited Friday evening and fueled by brush and grass was at more than 700 acres (283 hectares) Sunday and still with zero containment.

BLM spokeswoman Dolores Garcia declined to discuss any aspects of the plane crash Sunday, saying investigators from the National Transportation Safety Board, the Federal Aviation Administration and the Interior Department’s Office of Aviation Services will try to determine the cause.

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“We don’t have answers right now. We hope to get them in the coming days,” Garcia said.

The Arizona Republic quoted a 54-year-old Wikieup woman who said she saw the plane going down at a “steep angle” before hitting the ground.

Michele Machholz said she was looking outside from her kitchen while talking to her husband on the phone and thought she saw a turkey vulture before realizing it was a plane.

“And it’s coming down at an angle that … you don’t traditionally see airplanes flying at,” Machholz told the Republic.

Machholz said she then watched the plane “slam into the ground.”

“I’m screaming on the phone, ‘And, oh my gosh, it just crashed! I can’t believe it,’” she said. “I’m trying to tell my husband that this airplane just crashed and there was this big, black plume of giant, black smoke.”

Machholz declined an interview request Sunday when reached by The Associated Press.

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“I’m a retired photojournalist for 30 years, and I don’t wish to relive the horror of yesterday,” said Machholz, 54. “I will state this: There’s an enormous difference between covering disasters on assignment as a journalist and witnessing them live in front of you… I am in a state of shock still.”