2 young kids and father among 5 dead in crash of truck carrying anhydrous ammonia

A father and his two young children were among five killed in a multi-vehicle crash in Illinois involving a semi-truck transporting potentially toxic anhydrous ammonia, police said.

At about 9:25 p.m. Friday, Sept. 29, police responded to a crash on U.S. Highway 40 near Teutopolis, Illinois, which is located about 2 hours southeast of Springfield. The semi-truck started leaking anhydrous ammonia after rolling over into a ditch, Illinois State Police said.

Approximately 500 people from the surrounding area have been evacuated due to the leak, and were expected to return to their homes the morning of Sunday, Oct. 1, according to the Illinois Environmental Protection Agency.

Effingham County Coroner Kim Rhodes said Saturday, Sept. 30 that five people were killed and five more were airlifted to area hospitals following the crash and spill.

The coroner later confirmed that a father and his two children, both under age 12, were among those dead. The identities of the family members, and the other victims in the crash, were not provided, but Rhodes said two were from out of state.

The cause of death is still under investigation, police said.

Anhydrous ammonia is a clear, colorless gas with a "very characteristic odor" that can cause severe damage to the eyes and lungs, and lead to death, according to the North Dakota State University Department of Agriculture.

The chemical is considered to be "one of the most dangerous" substances used in agriculture in the modern day, the department noted.

"At a concentration of only 50 parts per million (ppm), one sniff tells what is in the air. Normally, the odor will drive a person away from the area," the university reported. "A concentration of more than 5,000 ppm will disable a person so that escape is impossible and suffocation results."

According to the Illinois EPA, the truck was carrying approximately 7,500 gallons of anhydrous ammonia at the time of the accident with about 4,000 gallons released during the leak. Officials say the leak has been partially patched.

A 15-person team, including "motor carrier, hazmat and survival factors investigators," were expected to arrive to the scene Saturday night, NTSB spokesperson Jennifer Gabris said.

This article was originally published on TODAY.com