An injured displaced civilian, who fled the ancient city of Palmyra after Islamic State fighters took control of the area, stands inside a tent as he holds up a mobile phone showing a picture of his cousin, whose throat was cut by Islamic State fighters, according to him, in Gazaleh town, north of Homs June 3, 2015. The government has lost large areas of land in the last two months to insurgents including the al Qaeda-linked Nusra Front and the Islamic State group that last month seized the ancient city of Palmyra in Homs province. Picture taken June 3, 2015. REUTERS/Omar Sanadiki 

Displaced civilians, who fled the ancient city of Palmyra after Islamic State fighters took control of the area, walk in Gazaleh town, north of Homs where they are taking shelter June 3, 2015. The government has lost large areas of land in the last two months to insurgents including the al Qaeda-linked Nusra Front and the Islamic State group that last month seized the ancient city of Palmyra in Homs province. Picture taken June 3, 2015. REUTERS/Omar Sanadiki 

Displaced children, who fled the ancient city of Palmyra after Islamic State fighters took control of the area, stand by their tent in Gazaleh town, north of Homs June 3, 2015. The government has lost large areas of land in the last two months to insurgents including the al Qaeda-linked Nusra Front and the Islamic State group that last month seized the ancient city of Palmyra in Homs province. Picture taken June 3, 2015. REUTERS/Omar Sanadiki 

Displaced Iraqi Sunnis fleeing from Islamic State militants in Anbar province, receive aid supplies at Camp Habbaniyah between the cities of Fallujah and Ramadi, March 12, 2015. Picture taken March 12, 2015. REUTERS/Alaa Al-Marjani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT SOCIETY TPX IMAGES OF THE DAY) 

A boy from the minority Yazidi sect looks on in the outskirts of Kirkuk January 17, 2015. Islamic State freed around 350 members of Iraq's Yazidi minority on Saturday, delivering them to safety in the country's Kurdish north. REUTERS/Ako Rasheed (IRAQ - Tags: POLITICS MILITARY CIVIL UNREST CONFLICT SOCIETY) 

Displaced women sit outside of their tent at Camp Habbaniyah between the cities of Fallujah and Ramadi, March 12, 2015. Picture taken March 12, 2015. REUTERS/Alaa Al-Marjani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT SOCIETY) 

A Yazidi refugee girl washes her tent at Sharya refugee camp on the outskirts of Duhok, March 4, 2015. REUTERS/Asmaa Waguih (IRAQ - Tags: POLITICS CIVIL UNREST CONFLICT SOCIETY) 

Yazidi refugees sell chickens at a refugee camp on the outskirts of Duhok, February 28, 2015. Picture taken February 28, 2015. REUTERS/Asmaa Waguih (IRAQ - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION ANIMALS) 

A Yazidi refugee gets a hair cut in a tent used as a barber's, at a refugee camp on the outskirts of Duhok, February 28, 2015. Picture taken February 28, 2015. REUTERS/Asmaa Waguih (IRAQ - Tags: CIVIL UNREST CONFLICT SOCIETY IMMIGRATION) 

A Yazidi man kisses the ground of a Yazidi temple in Lalish, Sheikhan province, Kurdistan region, northern Iraq, February 28, 2015. Tens of thousands of the Yazidi minority sect in Iraq have been displaced after attacks by the Islamic State militant group since last August. Picture taken February 28, 2015. REUTERS/Asmaa Waguih (IRAQ - Tags: RELIGION) 

Displaced Iraqi Sunnis fleeing from Islamic State militants in al-Baghdadi district in Anbar provinces, receive aid from the United Nations Refugee Agency (UNHCR) in Baghdad February 24, 2015. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS SOCIETY IMMIGRATION) 

Displaced Iraqi Sunni children from Anbar province, study at Camp Habbaniyah between the cities of Fallujah and Ramadi, March 12, 2015. Picture taken March 12, 2015. REUTERS/Alaa Al-Marjani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT SOCIETY EDUCATION) 

Yazidi refugees smoke a water pipe at at refugee camp in the outskirts of Duhok, February 27, 2015. REUTERS/Asmaa Waguih (IRAQ - Tags: POLITICS SOCIETY IMMIGRATION CIVIL UNREST CONFLICT) 

Yazidi refugees play volleyball at Sharya refugee camp on the outskirts of Duhok March 4, 2015. REUTERS/Asmaa Waguih (IRAQ - Tags: POLITICS CIVIL UNREST CONFLICT SOCIETY)