Soldiers from 3rd Armored Brigade Combat Team, 4th Infantry Division, conduct a tank live-fire and react-to-fire exercise on Adaui military base, Latvia, as a part of Operation Atlantic Resolve, Sunday, April 9 2017. Four soldiers are in good condition after being treated for carbon monoxide exposure when their M1A2 Abrams tank malfunctioned on an exercise, the military said. (Charlene Moler/U.S. Army)

Four U.S. Army soldiers are in good condition after being treated for carbon monoxide exposure when their M1A2 Abrams tank malfunctioned on an exercise in Latvia, the military said.

The incident occurred on Sunday, and soldiers were sent to a hospital in Latvia’s capital of Riga for treatment, U.S. Army Europe said.

Three soldiers, assigned to the 3rd Armored Brigade Combat Team, 4th Infantry Division, have since reported back to their camp in Latvia for duty. A fourth soldier, transported to Landstuhl Regional Medical Center in Germany for further observation, is in good condition, USAREUR said.

“Soldier safety is the brigade’s top concern, and all tank crews are testing exhaust systems to ensure no further incidents occur,” USAREUR stated.

In January, the Fort Carson-based 3rd Brigade left Colorado for Europe, where the unit is on a nine-month deployment. The unit’s tanks and other heavy vehicles traveled by ship and rail before landing in Poland.

The deployment marked the beginning of an Army plan to maintain a year-round presence of a tank brigade in Europe.

Since the arrival of the 3rd Brigade the unit has been spread out along NATO’s eastern flank to conduct a continuous series of exercises with allies stretching from Estonia to Romania.

The 3rd Brigade is expected to be replaced by another unit when it ends its tour.

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