FREMONT, Nebraska, USA- Three people were inside the plant at the time of the explosion, Fremont Mayor Joey Spellerberg said during the briefing, adding, "But that's all we could say at this point."
Due to the structural collapse, fire crews have been unable to access the building to conduct a search, Bernt said.
"Early on, we tried to get access, but just due to the collapse with the mangled steel, we were unable to get inside," Bernt said.
Due to the structural issues, the fire department requested support from Nebraska Task Force One, which is assessing how to safely conduct a search, the chief said.
The fire remained active Tuesday afternoon, especially in the facility's tower, according to Bernt, who said he expects fire crews to be on site for several days.
Bernt said the plant has a lot of wood and some alcohol-based materials stored inside.
The cause of the explosion remains under investigation. The Nebraska State Fire Marshal's Office and other agencies are on scene.
Spellerberg said multiple agencies have responded to the explosion.