IS strikes: Khorasan Group also targeted, says Pentagon

US President Obama has hailed the support of Arab nations in air strikes on Islamic State (IS) militants, saying: "This is not America's fight alone."

He was speaking hours after the US and Arab allies launched their first air strikes against IS in Syria.

Speaking to reporters at the Pentagon, the director of operations for the US Joint Chiefs of Staff, Lieutenant General William Mayville, said al-Qaeda-linked militants, known as the Khorasan Group, were also targeted by eight air strikes in Syria.