Iraqi forces are digging in to battle Islamic militants on the outskirts of the oil city of Kirkuk. Fighters from the Islamic State in Iraq and the Levant have already overrun Saddam Hussein's hometown of Tikrit and taken Mosul, the country's second largest city 90 miles away. The only sign of the Army and police are their uniforms, abandoned as they fled.
Elizabeth Palmer reports on the challenge to Iraq's Shi'ite-led government. Watch video above.