Eighteen people are missing after a blast at a military explosives manufacturing facility in Tennessee on Friday.
Humphreys County Sheriff Chris Davis said one person initially believed to be on site had been located at home. Four or five people were taken to a nearby hospital after the enormous explosion that levelled the factory.
There's nothing to describe, it's gone, he said.
The plant in Bucksnort, Tennessee - roughly 56 miles (90km) south-west of Nashville - specializes in the development, manufacture, handling, and storage of explosives. The cause of the blast remains unclear.
Aerial video from the scene showed charred debris, smouldering vehicles and little remaining of the facility, which is owned by Accurate Energetic Systems.
During the initial media briefing, Sheriff Davis, who was visibly emotional, confirmed that 19 individuals were unaccounted for and that the explosion occurred in a large building, sending debris across a half square mile.
Workers who had just started their day now may be missing or deceased according to Davis.
Tennessee Governor Bill Lee remarked on social media about the incident being tragic and mentioned ongoing monitoring of the situation while state and local authorities collaborate with federal agencies to address the aftermath.
The factory, covering about 1,300 acres, produced C-4 and TNT, and ceased operations following the incident, which has drawn a massive response from law enforcement, including the FBI and ATF.
As investigations commence, officials have warned that this may take a significant period, as teams work slowly and methodically to determine the cause of the blast.