FORT BLISS, Texas (NewsNation Now) — 11 Fort Bliss soldiers are under medical care after ingesting ethylene glycol, otherwise known as antifreeze, believing it was alcohol at the end of a 10-day training exercise Thursday.

Two remain in critical condition, NewsNation affiliate KTSM-TV reported.

The unit was completing a field training exercise on Thursday when the incident occurred, according to a news release. One warrant officer, two noncommissioned officers, and eight enlisted members were injured.

The soldiers are being treated at William Beaumont Army Medical Center, according to Fort Bliss officials.

“We took immediate action to treat everyone involved with the best medical care available,” Maj. Gen. Sean C. Bernabe, senior mission commander of the 1st Armored Division and Fort Bliss, said in a statement to the media. “Our leaders are engaged at every level to provide guidance, information and care for their teammates. Our commitment to our soldiers and families remains our No. 1 priority as we work to understand what occurred Jan. 28.”

The incident was first reported after Fort Bliss officials said they had ingested an “unknown substance during a field training exercise” on Thursday.

An investigation into the incident was opened by officials.

Fort Bliss leaders said they are updating the soldiers’ families and unit members, as well as cooperating with law enforcement, who are investigating the incident.

The U.S. Army Post is located in Texas and New Mexico, with its headquarters in El Paso, Texas.

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