Two people were killed in an explosion at a feed-processing factory in the United States, CNN reported.
It happened Monday at International Nutrition Inc, a plant that produces animal and poultry feed in Omaha, Nebraska, dpa reported.
"I just heard a crack pop and big ball of fire, and I just took off running when I heard the first crack," Jamar White, a worker at the plant, told broadcaster KETV.
Thirty-eight people were in the plant at the time, Omaha fire chief Bernard Kanger said.
Ten people were hospitalised and seven others treated at the scene, he said.
Kanger said the cause of the incident was being investigated.
"What we do know is there was a significant event that occurred, causing catastrophic failure of the structure," he said.
The second and third floors of the plant collapsed.
About 50 firefighters responded to the emergency.