The Iraqi military says U.S.-backed Iraqi special forces have entered the city limits of Mosul as part of its campaign to retake control of the city from ISIS. The United States is backing the Iraqi army with both U.S. special forces on the ground, as well as U.S. airstrikes. On Tuesday, the Iraqi military said it has taken control of Mosul’s television station.

Talib Shaghati: “Our troops entered the Mosul TV station. The Mosul TV station is very significant. It means the city of Mosul. And this is good news for the people of Mosul, indicating that the real operation to liberate Mosul has begun.”

The United Nations is warning as many as 1 million civilians could be displaced amid the fighting for control of Mosul—leading to what could become the largest humanitarian crisis in Iraq’s history.