At the same time, American troops in Stryker fighting vehicles and armored Humvees flying large American flags began to appear in and around Manbij to dissuade Turkish-backed militias and other groups from attacking the area. The American troops include a unit of Army Rangers, who appear to have been sent to northern Syria from the base American forces use in Erbil, Iraq. It was an unusually public role for Army Rangers, who often prefer to operate in the shadows.