BBC Online :The US has carried out a series of air strikes on Islamic State militants close to the vital Haditha dam in western Iraq, US officials say.The US strikes, the first in the area, were to protect the Iraqi forces and Sunni tribesmen in control of the dam.The US has carried out scores of air strikes to support Iraqi and Kurdish forces as they try to halt the advance of the militants in the north and west.Earlier, Kurdish forces retook the strategically important Mount Zarta.The American air attacks, the first of their kind in Anbar province, signal that Washington has crossed a line that it itself drew.It has long had a standing request from the outgoing Iraqi government to use its air power against IS in all areas. But until recently, it made it clear it would only do that once a new, inclusive government is formed in Baghdad, with full Sunni representation.That hasn’t yet happened, though intensive efforts are under way to produce a new cabinet in the coming days.A US official said: “At the request of the Iraqi government and in keeping with our mission to protect US personnel and facilities, US military planes have begun striking Isil terrorists near the Haditha dam.”The Pentagon’s press secretary, Rear Admiral John Kirby, later said: “We conducted these strikes to prevent terrorists from further threatening the security of the dam, which remains under control of Iraqi security forces, with support from Sunni tribes.”IS, also often referred to as Isil or Isis, has taken over large swathes of Iraq and Syria in recent months, declaring the land it holds a “caliphate”.Kurdish forces at the Mosul dam, 21 Aug US air strikes helped Kurdish forces dislodge IS militants from the Mosul dam. The US has now carried out more than 130 air strikes since early August.Islamic State fighters have targeted a number of dams in their offensive, capturing the facility at Fallujah.They also took the largest dam, at Mosul, but US air strikes helped force them out.The group has so far failed in its attempts to capture Haditha dam, on the Euphrates valley in western Anbar province. It is Iraq’s second largest dam.IS militants in August reportedly closed eight of the Fallujah dam’s 10 lock gates that control the river flow, flooding land up the Euphrates river and reducing water levels in Iraq’s southern provinces, through which the river passes.