Fire crews are operating a prescribed fire in the Tres Rios Wetlands, filling southwest Valley skies with smoke that can be seen miles away.

Fire operations are underway on a 50-acre plot of the wetlands, about 16 miles southwest of downtown Phoenix, according to a social media post at 8:18 a.m. by the Arizona Department of Forestry and Fire Management.

Officials said the burn is a joint effort by Arizona DFFM and Phoenix Fire Department to reduce invasive plant species and overgrown vegetation in the 700-acre wetlands.

The wetlands are located in the area of 91st Avenue and Broadway Road in west Phoenix, near the Salt River, according to a city website.

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