Emergency responders work the scene of semitruck crash in Teutopolis, Ill., on Saturday. Federal regulators confirmed they are reviewing the crash of a semitruck carrying a toxic substance in central Illinois, resulting in

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Emergency responders work the scene of semitruck crash in Teutopolis, Ill., on Saturday. Federal regulators confirmed they are reviewing the crash of a semitruck carrying a toxic substance in central Illinois, resulting in "multiple fatalities" and dangerous air conditions that prompted the evacuation of area residents. / NewsNation-WTWO via AP

Updated October 1, 2023 at 4:43 AM ET

SPRINGFIELD, Ill. — Five people were killed and five were seriously injured after a truck overturned in central Illinois, causing a toxic substance to leak from its cargo and forcing the evacuation of hundreds of area residents, authorities said Saturday.

A semitruck carrying caustic anhydrous ammonia toppled about 9:25 p.m. Friday night in Teutopolis, spilling more than half its 7,500-gallon (28,390-liter) load, according to the Illinois Environmental Protection Agency.

Effingham County Coroner Kim Rhodes said the five dead included three from the same family: one adult and two children under 12. The other two were adult motorists from out of state, Rhodes said. Additionally, five people were airlifted to hospitals, their conditions unknown.

Names of the victims were not released, nor would authorities discuss causes of death.

About 500 residents within a 1-mile (1.6-kilometer) radius of the crash site were evacuated after the accident, including northeastern parts of Teutopolis. Late Saturday night, Teutopolis Fire Protection District Assistant Chief Joe Holomy said testing found the area was safe for residents to return home.

Emergency crews worked overnight after the accident on Friday trying to control the plume from the leak and struggled to get near the crash site.

"We have a lot of brave firemen, EMT, hazmat specialists, police officers that are working on this scene as we speak," Effingham County Sheriff Paul Kuhns said at a Saturday morning news conference.

As of midday Saturday, the accident scene was still heavily blockaded. Kuhns apologized for any inconvenience from the investigation and the evacuation.

Private and federal environmental contractors were summoned to recommend a cleanup procedure in Teutopolis, a town of 1,600 about 110 miles (177 kilometers) northeast of St. Louis.

The National Transportation Safety Board will review the crash, spokesperson Jennifer Gabris told The Associated Press.

The accident caused "a large plume, cloud of anhydrous ammonia on the roadway that caused terribly dangerous air conditions in the northeast area of Teutopolis," Kuhns said. "Because of these conditions, the emergency responders had to wait. They had to mitigate the conditions before they could really get to work on it, and it was a fairly large area."

Although not strong, crews working overnight struggled against shifting wind.

"The wind changed three or four different times on us," said Tim McMahon, chief of the Teutopolis Fire Protection District. "That's another reason we got crews out in different places, reporting back on which way the wind's going."

Traffic, including the tanker, was pushed onto U.S. 40, which bisects Teutopolis, earlier Friday because of another truck crash on Interstate 70.

Phillip Hartke, 75, who lives in Teutopolis but farms with his son outside of town, said U.S. 40 was jammed after the I-70 closure. Hartke finished harvesting corn about 9:30 p.m. Driving home, as he neared the center of town, he could smell anhydrous ammonia. When he reached U.S. 40, emergency vehicles swarmed the area.

"Firefighters advised us right there: 'Evacuate to the west,'" Hartke said.

Hartke estimated 85% of Teutopolis was subject to the evacuation. He and his wife were staying with his son. Such familial ties should serve most evacuees well.

"'T-Town' is a tight-knit community," Hartke said. "Many people have sons and daughters, aunts and uncles within five or six miles of town."

Anhydrous ammonia is used by farmers to add nitrogen fertilizer to the soil and as a refrigerant in the cooling systems of large buildings such as warehouses and factories. According to the American Chemical Society, it is carried around the United States by pipeline, trucks and trains.

In 2019, dozens of people were sickened in suburban Chicago after the valves were left open on tanks of anhydrous ammonia being transported from a farm in Wisconsin to one in Illinois, creating a toxic gas cloud and sickening dozens of people. Seven people were initially hospitalized in critical condition after a leaking anhydrous ammonia tank pulled by a tractor released the plume over Beach Park.

And in 2002, a train derailment released anhydrous ammonia in Minot, North Dakota, killing one man, and hundreds of other people reported injuries including burns and breathing problems.

"It's terrible. It's bad stuff if you are involved in breathing it, especially because it gets in your airways, in your lungs, and it burns," Kuhns said.

In addition to having a commercial driver's license, the person behind the wheel of a toxic-substance tanker must study further and successfully complete a test for a hazardous material endorsement, said Don Schaefer, CEO of the Mid-West Truckers Association.

"Once you get that endorsement, there are no restrictions — unless otherwise posted — on hauling hazardous materials on a public highway," Schaefer said. "But you're subject to higher scrutiny."

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