An out-of-control forest fire grew to 19,200 acres on Wednesday and claimed its first structure, an abandoned hunting cabin.

The log cabin was destroyed as a 220-person force continued to battle the six-day-old blaze, which had shifted back in a southerly direction overnight, propelled by winds off Lake Superior.

In preparation for the wind shift, crews a day earlier completed a wide firebreak opening on the southern perimeter to prevent the fire from threatening the village of Newberry, seat of Luce County in the eastern portion of the Upper Peninsula.

Personnel from the Michigan Department of Natural Resources, U.S. Forest Service, local volunteer fire departments and the Wisconsin DNR composed the force battling the fire, believed to have been ignited Aug. 2 by lightning.

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Thus far, firefighters on the ground had focused on building fire lines, igniting backburns, protecting dwellings and taking other steps to create access for equipment, while the job of dumping water on the fire was left to aerial tankers, said Michigan DNR spokeswoman Ann Wilson.

But on Wednesday, she said, ground crews were ready to begin directly attacking the flames thanks to more favorable weather conditions, including rain showers that fell Tuesday night.

"Now, we'll start getting in there and aggressively battling it," she said.

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