The U.S. has started to withdraw equipment, but not troops, from Syria, the Defense Department clarified on Friday, amid early reports that the first personnel were pulled back into Iraq. Last month, President Donald Trump shocked allies and advisers by announcing the pullout. Early Friday, Col. Sean Ryan, spokesman for the U.S.-led coalition fighting ISIS, told the AP that the U.S. had started “the process of our deliberate withdrawal” from Syria, adding: “Out of concern for operational security, we will not discuss specific timelines, locations, or troop movements.” The Syrian Observatory for Human Rights, a British-based watchdog that monitors the conflict, said the withdrawal began late Thursday night when a convoy of armored vehicles pulled out from Syria’s northeastern town of Rmelan into Iraq. However, The New York Times reported hours later that two Defense Department sources insisted that no U.S. troops had been pulled out and their may in fact increase for security purposes as the exit could take as long as six months to complete. The pullout comes after Turkey threatened to attack Syrian Kurds—who have been America’s partners in the war against ISIS—when the U.S. withdraws. There are 2,000 American troops in Syria. Defense Secretary James Mattis resigned the day after Trump’s withdrawal announcement.