The apparent seriousness of Thursday afternoon’s accident at MagnaGro fertilizer plant, 600 E. 22nd St., escalated quickly.

As one ambulance was responding to a 911 call about a fall, more information came into dispatchers that changed responders’ mindset.

“Once we got there, it was a little bit different from what we anticipated from the callers,” said Mark Bradford, chief of Lawrence-Douglas County Fire Medical. “It escalated quite quickly from a single ambulance response on a fall to two critical patients in an unknown hazardous materials environment.”

With the investigation still under way, it’s still not been determined exactly how the two men — Roy Hillebert, 51, of Eudora, and Brandon Price, 25, of Lawrence — ended up in the chemical tank. The men, who worked at MagnaGro, died in the incident. Another worker who was injured was treated and released Thursday at Lawrence Memorial Hospital.

Authorities with LMH have identified the substance the two men were in contact with as cane molasses. The substance, often used in making fertilizer, isn’t believed to be dangerous in a well-ventilated environment, but when used in small spaces it can emit gases, including carbon monoxide.

Bradford said Friday that his emergency medical responders work each and every call to keep themselves safe. As crews exited the MagnaGro building on Thursday, they were washed off by other firefighters.

“Our initial entry people donned what we would normally wear in structure fires,” Bradford said. “It’s what we call our structural firefighting gear and they had a self-contained breathing apparatus on. That protects them, to a certain level, on all of their skin surfaces, and of course, we are protecting the respiratory.”

Bradford said he believes Fire Medical workers did all they could to save the lives of the men inside the MagnaGro plant.

“Overall, I think that what the men and women did on the department was a very appropriate response,” Bradford said.