TEUTOPOLIS, Ill. (WCIA) — An initial report from the National Transporation Safety Board is revealing new information about a tanker truck crash that resulted in a deadly hazardous materials leak in Teutopolis last month.

Five people died in the disaster, all from exposure to the anhydrous ammonia that leaked out of the crashed tanker. A further seven people were hurt, two of whom were still hospitalized as of Monday.

The NTSB found that the Sept. 29 crash was caused by a car trying to pass the truck in a no-passing zone, right as another car was driving the opposite direction. To avoid a collision between the two cars, the truck driver said he steered to the right.

The truck went off Route 40 and into a roadside ditch, hitting a 12-inch metal culvert in the process. The truck jackknifed and rolled onto its right side.

​​Aerial image of crash scene showing final rest positions of truck-tractor cargo tank semitrailer combination and utility trailer. [2] (Source: Illinois State Police; annotated by NTSB)

NTSB officials said the exposed front of the tanker then hit the tow ring of a utility trailer that was parked at the scene of the crash. The ring tore a hole into the tanker, allowing half of the anhydrous ammonia inside to leak out as a toxic cloud of gas.

Officials added that at the scene of the crash, Route 40 is a non-divided, two-lane asphalt road. Each lane is 12 feet wide with shoulders three feet wide.

The crash remains under investigation, and the NTSB intends to issue safety recommendations to prevent similar events.

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