The jihadist group Islamic State of Iraq and the Levant (Isis) has seized the Iraqi city of Mosul and looted $429m, becoming the world's richest terror group.
IBTimes UK looks at the history of this rebel group whose recent seizure in Iraq has caused more than 500,000 people to flee.
Origins of the group
Isis, known also as Isil, was founded in Iraq in 2013.
Isis originated from the merger of two other terror groups.
In April 2013, Abu Bakr al-Baghdadi (the current leader of Isis) released an audio statement in which he announced that AQI (Al-Qa'ida in Iraq) and Jabhat al-Nusra terror groups were officially merging under the name "Islamic State of Iraq and Al-Sham (the Levant)."
AQI had officially pledged allegiance to Osama bin Laden's network in October 2004.
Isis also expanded to Syria, but it operates independently of other Syrian jihadist groups such as the al-Nusra Front, the official al-Qaida affiliate in the country.
Baghdadi sought to merge with al-Nusra, which rejected the deal, and the two groups have operated separately since.
Isis engages in fighting with government forces over the hegemony of the territory of Iraq, Syria and Lebanon.
Isis fights against government and military targets, and has claimed responsibility for attacks that have killed thousands of Iraqi civilians.
In March 2013, it took over the Syrian city of Raqqa - the first provincial capital to fall under rebel control.
In January 2014, it took control of the predominantly Sunni city of Fallujah, in the western province of Anbar, Syria.
Isis fighters are highly motivated, battle hardened and well-equipped, analysts say.
"It also runs the equivalent of a state. It has all the trappings of a state, just not an internationally recognised one," Douglas Ollivant of the New America Foundation, told the Washington Post.
The group is widely known for its brutal rule in the areas that it controls.
Its latest attack in Mosul has sparked global outcry.
Abu Bakr al-Baghdadi
The organisation is led by Abu Bakr al-Baghdadi. Little is known about him, but it is believed he was born in Samarra, north of Baghdad, in 1971 and joined the insurgency that erupted in Iraq soon after the 2003 US-led invasion.
His real name is believed to be Awwad Ibrahim Ali al-Badri al-Samarrai. He holds degrees in Islamic Studies, including poetry, history and genealogy, from the Islamic University of Baghdad.
He emerged as the leader of AQI in 2010, after its former leaders were killed in an attack by US and Iraqi troops.