The number of foreign fighters who have travelled to Syria and Iraq to join militant groups such as Islamic State of Iraq and the Levant (Isil) has more than doubled and could stand at 31,000, according to a new study.
The figures show the extent to which a jihadist movement that grew out of Iraq’s insurgency and Syria’s civil war has become a hub for international terror.
According to the Soufan research group and its vice-president, the former MI6 head of counter-terrorism Richard Barrett, the number of fighters has grown hugely since the beginning of the US-led bombing raids against the group in summer 2014.
In June of that year, when Isil surged across western Iraq seizing major cities including Mosul, it calculated there were 12,000 foreign fighters in the group. Now it believes that between 27,000 and 31,000 foreigners have joined up.
The number of countries from which they have come has increased from 81 to 86, while it also gives a figure for a “rate of return” - fighters coming back to western Europe and elsewhere. This, it says, stands at 20-30 per cent.
For Britain, it cites official estimates saying around 760 citizens have travelled to Syria, and around 350 have returned.
The war in Iraq followed Afghanistan in becoming a recruiting ground for jihadists from Muslim communities across the world, but most were from other Arab countries, some motivated by nationalist as well as religious feeling.
Most of the jihadists who have flocked to Syria too have been from the Middle East and Gulf countries (8,240) or North Africa (8,000).
However, 5,000 are thought to have come from western Europe, around double the number 18 months ago.
The fastest increasing group comes from Russia and other former Soviet bloc countries. Russian nationals - prominently including many Chechen fighters - number 2,400, similar to Saudi Arabia (2,500) but well behind Tunisia, which has sent the most at 6-7,000.
The rise in numbers suggests that the violent atrocities carried out by Isil in the last 18 months - the mass executions of thousands of Iraqi prisoners, the beheadings of Western and other captives, the burning alive of a Jordanian pilot - have only added to the group’s appeal. Nor has the loss of territory to the Kurds in the north damaged morale.
That suggests motives for joining up may be personal rather than political, the report said.
“The majority of [Isil’s] video production appeals to those who seek a new beginning rather than revenge for past acts,” the report says.
“A search for belonging, purpose, adventure, and friendship appear to remain the main reasons for people to join the Islamic State, just as they remain the least addressed issues in the international fight against terrorism.”
As well as Russia, the numbers travelling from Central Asia are also rising fast, showing Isil’s ability to foster new recruiting grounds, often via personal networks.
Around 300 are now said to have come from China. It has long been accused of driving its Uighur minority, an ethnically Turkish Muslim group, into the arms of jihadists by its policies in their region of western China.
The government in Beijing on the other hand has increasingly referred to opposition from the Uighurs as prompted by religious radicalism.
A new video uploaded to the Isil media arm, Al-Hayat Media Centre, contained a nasheed or religious chant in Mandarin, suggesting China is to be a new target.
The chant features the slogans “The shameless enemy would panic" and “It’s my dream to die on this battlefield”.
China has maintained a non-interventionist policy in the Middle East, and has opposed foreign military action in Syria.
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