Islamic State group: Crisis in seven charts
- 27 April 2016
- From the section Middle East
Militants from so-called Islamic State (IS) have seized large parts of Syria and Iraq, where as many as 10 million people live under their control.
In June 2014, the jihadist group overran the northern Iraqi city of Mosul, and then moved southwards towards Baghdad, routing Iraq's army and threatening to eradicate the country's many ethnic and religious minorities.
Two months later, after the militants advanced on the Iraqi Kurdish city of Irbil, the US launched air strikes on IS positions in Iraq. A multinational coalition led by the US extended the air campaign to Syria that September.
Since then, IS has lost approximately 40% of the populated territory it once held in Iraq, and 10-20% of the populated territory it had seized in Syria, according to the US.
The US also estimates that its air strikes have killed a total of 25,000 IS fighters.
In Iraq, the UN says more than 18,800 civilians were killed in acts of terrorism and violence between January 2014 and October 2015.
The picture is less clear in Syria. However, the UK-based Syrian Observatory for Human Rights reported in early 2016 that IS had summarily killed 3,967 people since June 2014, and that at least 366 civilians and 3,914 IS militants had been killed in US-led air strikes.
The US-led coalition has launched more than 7,800 air strikes against IS targets in Iraq since August 2014.
The UK launched its first air strikes on the group in Iraq the following month. Other nations taking part include Australia, Belgium, Canada, Denmark, France, Jordan, and the Netherlands.
In Syria, the US-led air campaign began in September 2014. Since then, more than 3,600 strikes have been carried out by coalition forces, which include Australia, Bahrain, Canada, France, Jordan, the Netherlands, Saudi Arabia, Turkey, United Arab Emirates and the UK.
Russia is not part of the US-led coalition, but its aircraft began carrying air strikes against what it called "terrorists" in Syria a year later.
President Vladimir Putin insists his forces have bombed only IS, the al-Qaeda-affiliated al-Nusra Front and other groups designated as terrorist organisations by the UN. However, activists say Russian aircraft have mainly hit mainstream Syrian rebel groups that are backed by Western powers and are violently opposed to IS.
The declaration of the formation of a "caliphate" by IS in June 2014 triggered a surge in the number of foreign fighters travelling to Syria and Iraq to join the group.
A report published in December 2015 by the New York-based security consultancy Soufan Group estimated that 27,000 foreign jihadists made the trip from 86 countries, more than half of them from the Middle East and North Africa.
Tunisians make up the majority of foreign recruits, driven by unemployment at home and disillusionment following the 2011 Arab Spring uprising that toppled long-time President Zine al-Abidine Ben Ali.
The conflict with IS has left some cities and towns across Syria and Iraq in ruins. Other areas have been cut off by IS militants, leaving their populations dependent on foreign aid and black-market food supplies.
A focus of the fighting in 2014 was the northern Syrian town of Kobane, on the border with Turkey. IS militants seized much of the town after launching an assault that September, but they were eventually driven back by Kurdish forces, backed by US-led coalition air strikes. The battle left more than 1,600 people dead and Kobane in ruins.
Ramadi in western Iraq also suffered widespread destruction during a months-long offensive by Iraqi government forces that saw IS militants driven out of the city in January 2016, eight months after overrunning it.
Another area seized by the militants has been Palmyra in Syria.
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IS captured the ancient city, which is a Unesco World Heritage site, is famed for its well-preserved Graeco-Roman ruins, in May 2015 and went on to destroy a number several of its best known buildings - including the two main temples and three funerary towers.
IS has ransacked and demolished several similar ancient sites that pre-date Islam in Iraq, denouncing them as symbols of "idolatry".
In March 2016, the Syrian army seized back Palmyra ending 10 months of occupation by IS, in what was seen as an important step towards the eventual defeat of the jihadist group.
IS has gained control of much of the oil infrastructure in Syria and Iraq, and oil is thought to be the group's biggest single source of revenue.
In October 2015, the US-led coalition stepped up air strikes aimed at halting the the oil extraction process in IS-held areas, targeting vehicles operating at the oil fields and facilities for pumping or moving oil as part of "Operation Tidal Wave II".
Reports suggest production has fallen since then - partly because IS does not have the technology to maintain aging equipment, and partly as a result of the coalition strikes.
Other sources of income for the group include taxes and property confiscation, as well as gains it made from grain silos, banks and oil storage facilities when it first overran the Syrian and Iraqi territory it now occupies.
More than 4.8 million Syrians have fled abroad to escape the fighting in Syria, according to UN reports. Most have gone to neighbouring Turkey, Lebanon and Jordan - but a growing number have tried to reach Europe.
Many continue to do so despite facing perilous journeys across the Mediterranean from Turkey and Libya, contributing to a growing migrant and refugee crisis across Europe.
Syrian refugees have also put pressure on local services and infrastructure in Iraq - which is already coping with the return of many Iraqi refugees from Syria.
In addition, the UN estimates there are more than 3 million Iraqis who have been forced to leave their homes to escape the conflict with IS and are displaced within the country.