(CNN) — The Arizona fire that has engulfed more than 5,000 acres was caused by a human, officials said.
But the precise cause of the fire remains under investigation, said Jeff Andrews, deputy fire staff officer for Prescott National Forest.
As of Tuesday night, the central Arizona fire was 0% contained. But no injuries nor any lost structures had been reported, forest officials said.
But the situation could get uglier Wednesday.
"Without a doubt, we're going to incur a pretty difficult day tomorrow with the wind," Andrews said Tuesday night.
The fire was reported Tuesday morning about 8 miles northwest of Prescott, Arizona. Prescott is about 100 miles north of Phoenix.
"Driving into town, the smoke is really horrendous. Just huge, huge overwhelming smoke," said Trudy Thompson Rice, spokeswoman for the American Red Cross' Grand Canyon chapter.
She said the Red Cross opened one emergency shelter and could open a second, if necessary.
"There is a steady stream of vehicles leaving the area," she said. "It was pretty much bumper to bumper. They are getting out of the fire area, which is exactly what they need to be doing.