Civilian boys stand amid a scene of wreckage in Mosul, a city in northern Iraq that fell to an al Qaeda splinter group.
Mosul was captured on June 10 by the Islamic State of Iraq and the Levant (ISIL) - a group of Sunni militants who aim to create a caliphate straddling the border between Iraq and Syria. They put security forces in the city to flight and have been making further gains in a rapid military advance against Iraq's Shi'ite-led government.
10 Jun 2014. ARBIL, Iraq. REUTERS/Reuters photographer
An estimated 500,000 Iraqis have fled Mosul and the surrounding province. Many, like the family pictured above, headed towards the nearby Kurdistan region, where Iraq's ethnic Kurds have autonomy and their own large and disciplined military force.
Turmoil in Iraq has grown further as ISIL rebels also overran the city of Tikrit on June 11 and closed in on the biggest oil refinery in the country.
30 May 2014. HASAKAH, Syria. Reuters/Massoud Mohammed
ISIL has risen to become a dominant player in both Iraq and Syria, where it has seized a string of cities over the past year, often fighting other Sunni groups.
The image above shows bodies of people whom activists said were killed by ISIL in a village near Ras al-Ain city in northern Syria - just one example of the carnage tearing through the region.
In Iraq, militants took Falluja and parts of Ramadi in the desert west of Baghdad at the start of the year. Now the fall of Mosul, a largely Sunni Arab city, deals a serious blow to the Iraqi government's efforts to fight their rise.
2 Apr 2014. BAGHDAD, Iraq. REUTERS/Alaa Al-Marjani
In the image above, Iraqi forces take part in clashes with ISIL south of Baghdad in April, after security in the country had long begun to deteriorate.
The United States, which pulled its troops out from Iraq two and half years ago, has pledged to help Iraqi leaders "push back against this aggression".
But the militants’ rapid advances indicate that Iraq's forces - trained and equipped by Washington at a cost of nearly $25 billion and numbering more than a million strong - are outmatched against their foes.
2 Apr 2014. RAQQA, Syria. REUTERS/Reuters photographer
In Syria ISIL has made enemies of several rebel groups since it seized control of many towns and checkpoints in opposition areas. The group's leader Abu Bakr al-Baghdadi (not pictured) has shown himself to be ruthless in eliminating opponents as he furthers his ambition of creating an Islamist state.
ISIL holds the city of Raqqa - Syria's only provincial capital completely beyond President Bashar al-Assad’s control - and has imposed strict laws, banning music and cigarettes and obliging women to wear a burqa or full veil.
In the image above, fighters with the group stand on confiscated cigarettes, ready to set them on fire.