PAYSON, Arizona- KPHO/KTVK is reporting fatalities and multiple injuries are confirmed in an explosion and huge fire in Payson.

Fire officials are calling it a “mass casualty assignment.”

The Payson Fire Department says there was a gas explosion around 8 p.m. at a four-unit apartment complex.

Crews from several cities are responding with fire trucks, and multiple ambulances were called to the scene.

Witnesses reported hearing a large explosion  and seeing flames.

“It was loud; rattled my windows,” reported one witness who heard the explosion.

ADOT tweeted that part of SR 87 was blocked due to fire trucks in the area.

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