Shiite fighters known as Hashid Shaabi walk as smoke rises from an explosives-laden military vehicle driven by an ISIS suicide bomber which exploded during an attack on the southern edge of Tikrit, Iraq, on March 12, 2015. #

A Shiite fighter launches a rocket during clashes with ISIS militants on the outskirts of al-Alam on March 8, 2015. Iraqi security forces and Shiite militia fighting the Islamic State took control of the center of a town on the southern outskirts of Saddam Hussein's home city Tikrit on Sunday, security officials said. #

Smoke billows as members of the Iraqi paramilitary Popular Mobilization units gather in the village of Albu Ajil, near the city of Tikrit, after they regained control of the area from ISIS jihadists on March 9, 2015. #

A member of militias known as Hashid Shaabi kneels as he celebrates victory while smoke rises from a clash with ISIS militants in the town of al-Alam on March 10, 2015. #

Members of Iraqi security forces and Shiite fighters sit on a vehicle in Al Hadidiya, south of Tikrit, en route to the ISIS-controlled al-Alam town, where they were preparing to launch an offensive on March 6, 2015. #

A member of the Iraqi paramilitary Popular Mobilization units, with "Daesh" (an Arabic acronym for ISIS) written on his boots, take part in a military operation in the village of Albu Ajil, near the city of Tikrit, on March 9, 2015. #

A military vehicle, belonging to Shiite fighters known as Hashid Shaabi, burns after being hit by ISIS militants, during clashes in northern Tikrit, on March 11, 2015. #

An Iraqi soldier takes photos of the demolished tomb of the former Iraqi president Saddam Hussein in Tikrit on March 15, 2015. The tomb of Iraq's late dictator was virtually leveled in heavy clashes between ISIS militants and Iraqi forces in a fight for control of the city of Tikrit. #

Members of the Iraqi paramilitary popular-mobilization units celebrate with an ISIS flag after retaking the village of Albu Ajil, near the city of Tikrit, on March 9, 2015. #

A picture taken from the village of Awja on the outskirts of the city of Tikrit on March 5, 2015, shows the palace of Iraq's former leader Saddam Hussein in the city of Tikrit. #

Members of a Shiite group, Asaib Ahl al-Haq, or League of the Righteous, flash victory signs during a funeral procession for six of their comrades who were killed in Tikrit fighting ISIS militants in Najaf, 100 miles (160 km) south of Baghdad, Iraq, on March 5, 2015. #

Shiite fighters known as Hashid Shaabi clash with ISIS militants, as one tries to put a Shiite flag in the ground, in northern Tikrit, on March 12, 2015. #

Volunteer Shiite fighters, known as the popular-mobilization units, who support the Iraqi government forces in the combat against ISIS fire a Howitzer in the village of Awaynat near the city of Tikrit on February 28, 2015. #

Smoke rises from an explosives-laden military vehicle driven by an ISIS suicide bomber which exploded during an attack on the southern edge of Tikrit on March 12, 2015. Iraqi security forces and mainly Shiite militia exchanged fire sporadically with Islamic State fighters in Tikrit on Thursday, a day after they pushed into Saddam Hussein's home city. #

A woman welcomes her brother who came as part of a militia known as Hashid Shaabi to the town of al-Alam on March 10, 2015. Iraqi troops and militias drove Islamic State insurgents out of al-Alam on Tuesday, clearing a final hurdle before a planned assault on Tikrit. #

A woman hugs her brother, a fighter with a militia known as Hashid Shaabi, as they are reunited in the town of al-Alam, on March 10, 2015. She had been living under ISIS rule for six months. #