Authorities report no survivors have been found following a devastating explosion at a Tennessee explosives plant, as efforts to retrieve remains remain ongoing.

“More than 300 personnel have thoroughly searched this entire facility, and as it stands, we have located no survivors,” Humphreys County Sheriff Chris Davis stated during a press conference.

Davis would not share how many people were killed in the Friday-morning blast, saying, “We’re in the process of the identification of the remains.”

“While it seems plausible, or rather necessary to use the term, I regretfully have to assume that those individuals are no longer alive,” he continued.

Davis said that the cause of the blast at Accurate Energetic Systems near McEwen is still under investigation, and that he cannot rule out foul play.

“That might be days or weeks or months before we can do that,” he said.

The blast happened at around 7:45 a.m. Friday morning and “encompassed one whole building,” according to Davis.

Officials had initially reported 18 individuals as missing following the event but offered no further specifics on Saturday, confirming only the absence of survivors.

Search operations at the site of the explosion continued overnight as officials notified families waiting on word about their loved ones.

Images from the site’s aftermath depict only scattered debris, with the plant completely demolished.

“As we get into this, we find it even more devastating than what we thought initially,” Davis said.

Special Agent Guy McCormick from the Bureau of Alcohol, Tobacco, Firearms and Explosives confirmed that certified explosives experts and bomb technicians are on-site to ensure area safety.

“In a situation like this, what we find is that when these explosives are subject to the event that took place — which is heat, the explosion being thrown, pressure — they can change, and they can become different than how we know them to act,” McCormick said on Saturday.

Accurate Energetic Systems on Friday extended thoughts and prayers in a statement to affected families, employees and community members. The privately owned facility, which processes ammunition and explosives, did not share any additional details on the explosion.

The facility established a family assistance center to provide support for those affected by the incident, according to the Tennessee Emergency Management Agency (TEMA).

There is no known threat to the public as a result of the blast, TEMA said. The agency is asking the public to avoid the area so emergency personnel can do their work “safely and efficiently.”

“Residents who locate debris that may have originated from the explosion are asked to contact their local sheriff’s office,” TEMA said. “Trained personnel will respond to ensure the safe handling and collection of any debris.”

The investigation into the incident is ongoing, officials said.

The FBI is also assisting with the investigation.