(CNN) Three US Green Berets were killed and two others were wounded in southwest Niger near the Mali-Niger border when a joint US-Nigerien patrol was attacked Wednesday, US officials told CNN. A US official told CNN that initial indications are the Green Berets were ambushed by up to 50 fighters who are thought to be affiliated with ISIS. US Africa Command, which oversees military operations in Africa, issued a statement Thursday saying the two wounded US service members were "evacuated in stable condition to Landstuhl Regional Medical Center in Germany." Officials told CNN that French military Super Puma helicopters evacuated the wounded Americans along with those killed in action while also providing covering fire.The US military has maintained a small presence in the northwest African countryThe attack occurred approximately 200 kilometers north of the country's capital Niamey
Five _ soldiers also were killed in the attack, according to a Nigerien security official.