RAPID CITY, S.D. (AP) — A firefighter killed by a wildfire in Northern California was apparently trapped by a sudden shift in the direction of the blaze, according to a new U.S. Forest Service report on his death.

Rapid City, South Dakota, firefighter Dave Ruhl was found in late July at the scene of the wildfire in Modoc National Forest. He was on a temporary assignment away from his regular duties as an engine captain in South Dakota.

The firefighter was driving down a road in a vehicle by himself, scouting the area, when the fire exploded.

The Rapid City Journal says the preliminary report on his death describes a fire that quadrupled in size within 30 minutes of crews arriving.

The wildfire scorched 7 1/2 square miles about a hundred miles south of Oregon. It's fully contained.

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