Crews are on the scene of a brush fire that is burning out of control in Pinal County on Wednesday.
When the fire was first reported, the Arizona Department of Forestry and Fire Management said the fire, now named the River Fire, had scorched about 30 acres near the Picacho Reservoir, which is 11 miles south of Coolidge.
At around 7 p.m., there were around 80 firefighters at the fire.
The agency said it should grow to a few hundred acres overnight because it's burning through salt cedar.
On Thursday morning, the fire increased 10 acres, to a total of 40 acres burned. However, the department said once daylight comes, they will have a better mapping of the fire and exact acreage.
No buildings are threatened.
However, some of the smoke could impact Coolidge.
It's unclear what caused the fire.