(AP) McGRATH, Alaska

A wildfire in interior Alaska has grown to 21,760 acres and is threatening more than two dozen structures.

Forestry spokesman Andy Alexandrou says more than 170 firefighters were battling the fire about 225 miles northwest of Anchorage on Thursday. More crews were on the way.

A total of 33 structures, mostly cabins along the Kuskokwim and Takotna rivers, were threatened.

There are at least two other wildfires in interior Alaska.

A nearly 1,900-acre blaze is burning about 20 miles southeast of Sleetmute. And another covering about 3 acres is burning about 100 miles northwest of McGrath, near the Innoko Wildlife Refuge boundary.

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