8,000 US soldiers accidentally gassed during morale-boosting activity

The event was intended to honour a Vietnam War-era battle

A member of the US Army’s 4th Infantry Division covers his mouth and nose to protect himself from CS gas after the irritant accidentally spread throughout a morale boosting event in Fort Carson, Colorado (Screengrab/TikTok/@Buffcity_)

Thousands of US Army soldiers were accidentally tear gassed during a "morale boosting" event on the day before Thanksgiving at For Carson, Colorado, according to Fox News.

The Army’s 4th Infantry Division was reportedly participating in a morale event honoring the battle of Dak To, a Vietnam-war era encounter in which the division participated.

Soldiers were tasked with running up hills, crawling through trenches, and climbing over obstacles as part of the event.

The Army holds similar events to remember historical battles, and — according Dee McNutt, a spokesperson for Fort Carson who spoke with Military.com — many of the events are designed to include an element of the unknown, in part to replicate the unpredictable nature of combat.

One of those unpredictable elements was the event organisers’ decision to use CS gas to mark the boundary of the course.

"The limited use of CS [gas] was not intended to interfere with the formations but to deter participants from leaving the course," Ms McNutt told the publication.

The problem with using the gas as a barrier is that — being a gas — it can be carried by the wind. As soldiers moved through the course, the winds changed and shifted the CS gas, which choked and disrupted the vision of many participants in the morale event.

Generally when soldiers are in a training situation in which they may be exposed to CS gas, they are warned ahead of time and advised to take precautions, like removing contact lenses, which can trap the gas between the lens and the eye, causing intense burning. Pregnant soldiers are also advised to avoid tear gas to avoid potential health risks.

However, because the CS gas was not intended to be an active part of the training, none of the participants were made aware that exposure was a possibility, leaving many affected soldiers to flee the event.

Video from the day of the event shows soldiers leaving the area with their eyes and mouths covered. Gas can be seen hanging in the air.