A deadly and “devastating blast” Friday morning at an explosives plant in Tennessee has left 18 people unaccounted for, authorities said.

Officials have said that multiple people were killed at Accurate Energetic Systems near McEwen, but Humphreys County Sheriff Chris Davis declined to give a number.

As of Friday night, the number of people who have not been accounted for dropped by one after a person who was believed to be at the site was found safely at home, Davis and Hickman County Sheriff Jason Craft said in a joint statement.

Davis appeared to be choking back tears as he spoke to reporters on Friday afternoon about the blast at the explosives plant, which supplies the military.

“It’s gone. It’s again, it’s the most devastating scene that I’ve seen in my career,” he said of what remains of the building.

It could take several days or even a week for first responders to dig through the rubble.

“Our hearts are with the families still waiting for word tonight,” Davis and Craft said in their statement. “We are doing everything possible to bring them information and support. We’re also deeply grateful to every responder and volunteer who has worked tirelessly throughout the day.”

The “devastating blast” occurred at 7:45 a.m. and “encompassed one whole building,” according to Davis.

Davis said in an evening update that officials don’t know what caused the explosion.

The plant sits on the line of Humphreys and Hickman counties, about 60 miles southwest of Nashville.

The facility processes ammunition and explosives, but does not manufacture them, the Tennessee Emergency Management Agency said.

Search operations at the blast site will continue overnight, and officials have been notifying families of those impacted throughout the day, Davis said.

He said the debris from the explosion spans about half a square mile.

The devastation is personal for the sheriffs of the two counties.

“We’re sitting in here and talking with these victims. I’m looking across these families, and I can tell you right off the top of my head that there’s three families that’s involved in this that I’m very close to,” Davis said in his evening update. “We’re small counties. And when you have small counties like this, we know each other, we communicate with each other, we love each other.”

Davis asked the public for prayers for the families.

Accurate Energetic Systems, founded in 1980, said its business in McEwen is “dedicated to the development, manufacture, handling, and storage of high-quality energetic products utilized in both defense and commercial markets.”

Accurate Energetic Systems has been awarded numerous military contracts, largely by the U.S. Army and Navy, to supply different types of munitions and explosives, according to public records. The products ranged from bulk explosives to landmines and small breaching charges, including C4.

When the explosion occurred, residents in Lobelville, a 20-minute drive from the scene, said they felt their homes shake and some people captured the loud boom of the explosion on their home cameras.

The blast rattled Gentry Stover from his sleep.

“I thought the house had collapsed with me inside of it,” he said by phone. “I live very close to Accurate and I realized about 30 seconds after I woke up that it had to have been that.”

TEMA said there’s no continuing threat to public health or safety from the explosives, though the public is urged to avoid the area.

A hotline has been established at 1-800-TBI-FIND or 1-800-824-3463 for missing persons reports.

Tennessee Gov. Bill Lee said his office is monitoring the situation.

“We ask Tennesseans to join us in prayer for the families impacted by this tragic incident,” he wrote on X.