FORT CARSON, Colo. (AP) — The Army says the last of a group of 150 Fort Carson soldiers is back in the United States after spending four months in Liberia helping to build treatment facilities to house Ebola patients and caretakers.

Officials said Wednesday about 10 soldiers arrived in the U.S. on Monday and will spend 21 days at Fort Hood, Texas, under medical observation.

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They were among 150 soldiers from Fort Carson’s 4th Engineer Battalion who deployed to West Africa in November.

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About 100 are back at Fort Carson after a 21-day monitoring period. Another group is being monitored at Joint Base Lewis-McChord, Washington.

During monitoring, medical personnel evaluate the soldiers daily, including twice-a-day temperature checks. The soldiers don’t have physical conduct with family members or other non-medical personnel.

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