Profile of Islamic State and leader, Abu Bakr al-Baghdadi

The rapid advance across Iraq of militant fighters from the Islamic State has thrown the country into chaos and led to US air strikes against their key positions.

Fighters from the group, which was formed in April 2013 under its former name Islamic State in Iraq and the Levant (Isis), have made substantial gains in northern Iraq in recent months, forcing tens of thousands of people from religious minorities to flee their homes.

BBC Newsnight's Secunder Kermani looks at the rise of the group and its leader, Abu Bakr al-Baghdadi.