Kurdish forces are now taking over large parts of Iraq's Mosul dam, and vow to continue fighting Islamic militants.
The Kurdish operation to take Iraq's largest dam was aided by US air strikes early on Sunday.
It comes after the Islamic State's (IS) capture of the facility on Aug 7.
An officer who did not give his name says nearly half the dam is now under Kurdish control.
"It is very important for the life in this area, for drinking water, for agriculture and other things. The other important thing, which is more important, is that if ISIS blows up this dam, then Mosul, Baghdad and other places will be damaged and will no longer exist."
If the Kurdish claim is confirmed, it will be the biggest reverse for IS since it launched its offensive in Iraq in June.
Meanwhile, Kurdish forces have called for more military supplies as they advance to retake key towns and the Mosul dam in northern Iraq.
Years of troubled relations between the Kurds and the central government in Baghdad has hindered the supply of arms.
Colonel Mahmoud Sangawe is a Kurdish commander for the Jalawla region.
"Actually, the government must help us fight, now that the war is on our land. After, the enemy will destroy their lands too. That is why."
Over the weekend, the UN Security Council adopted a resolution on sanctions against extremist groups in Iraq and Syria, in an attempt to cut off their external funding support.
