Iraqi forces say they have cleared Islamic State (IS) militants from a wide area around the strategic Haditha dam, helped by US air strikes.
The jihadists have repeatedly tried to capture the dam in western Anbar province from government troops and their Sunni militia allies.
The action marked a widening of US air strikes which have previously been in support of Kurdish forces in the north.
US President Barack Obama is to reveal a strategy on Wednesday to defeat IS.
The leader of a pro-Iraqi government paramilitary force in western Iraq said the air strikes wiped out an IS patrol trying to attack the dam.
“They (the air strikes) were very accurate. There was no collateral damage. If Islamic State had gained control of the dam, many areas of Iraq would have been seriously threatened, even (the capital) Baghdad,” Sheik Ahmed Abu Risha told Reuters.
“Joint forces backed by air support and tribesmen launched a wide attack to clear the areas surrounding the Haditha district,” security spokesman Lt Gen Qassem Atta told AFP news agency.
Troops and militia also retook Barwana, east of Haditha, from IS fighters, who abandoned their weapons and vehicles in their retreat, AFP reported.
However, the governor of Anbar, Ahmed al-Dulaimi, was wounded by a mortar round shortly after Barwana was retaken.
The US military said it carried out five strikes involving bomber and fighter aircraft.
It said militants’ armoured vehicles – some carrying anti-aircraft artillery – were destroyed. The US said all its aircraft left the area safely.
Haditha dam is Iraq’s second biggest hydroelectric facility and also provides millions with water.
The US has carried out more than 130 air strikes since early August to support Iraqi and Kurdish forces fighting IS in northern Iraq, but Sunday’s strikes were the first in Anbar.