- John Kerry, Chuck Hagel to visit India to push strategic tiesBarack Obama: Russia must press Ukraine rebels to allow Malaysia Airlines MH17 plane probeWhat are they trying to hide, cries Barack Obama even as Malaysia Airlines MH17 bodies, black boxes handed overObama, Abbott, Rutte, demand full access to MH17 crash site
U.S. warplanes bombed Islamist fighters marching on Iraq's Kurdish capital on Friday after President Barack Obama said Washington must act to prevent "genocide".
Islamic State fighters, who have beheaded and crucified captives in their drive to eradicate unbelievers, have advanced to within a half hour's drive of Arbil, capital of Iraq's Kurdish region and a hub for U.S. oil companies.
They have also seized control of Iraq's biggest dam, Kurdish authorities confirmed on Friday, which could allow them to flood cities and cut off vital water and electricity supplies.
A Pentagon spokesman said two F/A-18 aircraft from an aircraft carrier in the Gulf had dropped laser-guided 500-pound bombs on a mobile artillery piece used by the fighters to shell Kurdish forces defending Arbil.
Obama authorised the first U.S. air strikes on Iraq since he pulled all troops out in 2011, arguing action was needed to halt the Islamist advance, protect Americans and safeguard hundreds of thousands of Christians and members of other religious minorities who have fled for their lives.
The United States also dropped relief supplies to members of the ancient Yazidi sect, tens of thousands of whom are massed on a desert mountaintop seeking shelter from fighters who had ordered them to convert or die.
"Earlier this week, one Iraqi in the area cried to the world, 'There is no one coming to help'," said Obama in a late night television address to the nation on Thursday. "Well, today America is coming to help."
"We can act carefully and responsibly to prevent a potential act of genocide," he said. On Friday the White House said the strikes would last as long as the security situation required.
The Islamic State was defiant. A fighter told Reuters by telephone the U.S. air strikes would have "no impact on us".
"The planes attack positions they think are strategic, but this is not how we operate. We are trained for guerrilla street war," he said. "God is with us and our promise is heaven. When we are promised heaven, do you think death will stop us?"
The advance of the Sunni militants, who also control a third of Syria and have fought this past week in Lebanon, has sounded alarm across the Middle East and threatens to unravel Iraq, a country divided between Shi'ites, Sunnis and Kurds.
The U.S. airstrikes prompted renewed calls on jihadi online forums for attacks on the United States and oil interests in the Gulf. "The mujahideen must strive