A building is destroyed in an explosion at Northrop Grumman’s rocket test site

PROMONTORY, Utah (AP) — An explosion at Northrop Grumman’s remote rocket testing site in northern Utah destroyed a building Wednesday.

Officers found no injuries or fatalities in their initial investigation of the wreckage, according to the Box Elder County Sheriff’s Office.

Emergency crews had responded to reports of a loud blast and a dark plume of smoke rising over the rangelands at 7:38 a.m.

It was not immediately clear which building was destroyed and what its purpose was. The aerospace and defense company maintains a large presence in Utah, where it manufactures and tests solid rocket motors.

Northrop Grumman did not immediately release a statement.

The public is advised to avoid the area as officials continue to investigate.

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