Image: Officers guard the gate at Accurate Energetic Systems military explosives plant. Pic: Reuters
It scattered debris over at least half a mile (800m) and was felt by residents more than 15 miles (24km) away, Mr Davis said.
Aerial footage showed the company’s hilltop location smouldering and obliterated by smoke for much of Friday, with just a mass of twisted metal, burned-out shells of cars, and an array of debris left behind.
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Emergency services have been unable to fully attend the site due to secondary blasts.
Mr Davis described it as one of the worst scenes he had ever seen.
“What we need right now is we need our communities to come together and understand that we’ve lost a lot of people,” he said.
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The cause of the blast, which occurred about 60 miles southwest of Nashville, is not yet known but Mr Davis said it could be days, weeks or even months before foul play is ruled out.
Guy McCormick, a supervisory special agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives said experts need to make the area safe before specialist investigators begin combing through the remains.
He said the safety and security of the scene could change quickly because of the heat and pressure caused by the explosion.
Signs near the site on Saturday asked for prayers for the families.
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