The wildfire that started Tuesday afternoon just north of Sedona, near Slide Rock State Park, has grown to 4,500 acres.
The fire was about one-tenth that size 24 hours earlier.
According to the latest information released by the Forest Service, there were about 500 people fighting the fire as of last night, up from 200 the night before. Fifteen hotshot crews are among the people fighting the fire.
State Route 89 is still closed between northern Sedona and the southern edge of Flagstaff, and smoke has been drifting up to Flagstaff. The number of structures threatened by the fire has increased from 100 to 300.
The fire behavior is listed as "extreme," and the terrain for firefighters is listed as "very difficult."
Information from the Forest Service says there have been previous "fuel treatments" in the area, which are supposed to help control wildfires.
Fire investigators believe the fire is human-caused, although not much detail has been available about the circumstances. Here's what Forest Service officials wrote in yesterday evening's update:
Law Enforcement is seeking any information the public may have regarding the start of the Slide Fire and anyone of suspicion in the area yesterday between Slide Rock State Park and Half Way Picnic Area. The public should call Forest Service Law Enforcement at 928-527-3511 if they have any information that might assist law enforcement in the investigation.
The fire was at 0 percent containment, as of yesterday evening.
UPDATE 6:52 a.m.: Fire officials say this morning that the fire is as large as 4,800 acres.
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