Authorities said Saturday that the Mountain Fire had exploded in size to 7,225 acres in Tonto National Forest. Day-use areas and campgrounds near Horseshoe and Bartlett lakes have been closed and people that were already in those areas have been escorted out.
As of late Saturday morning, the fire was 20% contained, according to Arizona Interagency Wildfire Prevention. No homes are threatened.
The fire's massive plume of smoke reached more than 10,000 feet into the air and was detected on National Weather Service radar.
Air tankers and a helicopter were helping nearly 250 first responders fighting the fire. No further information has been released regarding the fire's cause.
The Associated Press contributed to this report.
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