'Oak Fire' near major highways was human caused, authorities say

Nearly 75 firefighters battled the Oak Fire near Highway 87 Sunday afternoon. It grew to about 5.5. acres, according to fire officials.

The fire broke out near Highway 87, south of Highway 188. Due to its closeness to the highways, the Department of Public Safety and the Gila County Sheriff's Office closed traffic partially, but it's been since reopened.

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"People need to be aware that overheated brakes, tow-chains, trailers, and mechanical issues can create a spark and lead to ignition,” said Brad Johnson, Tonto National Forest Central Zone Fire Management Officer.

The fire is expected to be 100% contained by the end of the Sunday.

No structures were threatened and no injuries reported.

Fire officials say the blaze was human-caused and is under investigation.

Firefighters also battled a 1,500-acre fire north of Phoenix, that is said to be human-caused.