Eleven soldiers at Fort Bliss, Texas, were injured Thursday after drinking antifreeze, believing they were drinking an alcoholic beverage, on the final day of a field training exercise, the Army said.
Two of the soldiers were seriously ill and have been moved to the intensive care unit at a hospital, Fort Bliss said in a statement. Nine others were at the hospital under observation.
Initial toxicology reports indicated they suffered from ethylene glycol poisoning, a substance commonly known as antifreeze, said Lt. Col. Allie Payne, a public affairs officer for the 1st Armored Division and Fort Bliss.
It was unclear how the soldiers ended up drinking the antifreeze.
Fort Bliss said that initial reports indicated the soldiers "consumed this substance, thinking they were drinking an alcoholic beverage." Payne said an investigation was immediately launched.
"We do want to understand what happened that day," she said at a news conference.
Soldiers are not allowed to drink alcohol while in a field training environment. They consumed the substance as they were leaving the training area at the end of the exercise, Payne said.
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One warrant officer, two noncommissioned officers and eight enlistees were injured in the incident, the Army said. All 11 were at William Beaumont Army Medical Center, where they have been since early Thursday afternoon.
"Our commitment to our Soldiers and Families remains our number one priority as we work to understand what occurred Jan. 28," Maj. Gen. Sean C. Bernabe, senior mission commander of the 1st Armored Division and Fort Bliss, said.