Iraq crisis: On the Baquba frontline with Shia militia
23 June 2014 Last updated at 22:50 BST
The US Secretary of State, John Kerry, has used a visit to Baghdad to call on Iraq's leaders to stand united against the Sunni militants, who have seized large swathes of the north and west of the country.
Much of the fighting is between the Isis extremists and Iraq's oldest Shia military, the Badr Army, which is intensely loyal to the government and has a history of violence against Sunnis.
The BBC's Jonathan Beale spent the day with the Badr Army on the outskirts of Baquba.