The surge of refugees arriving into Europe over the past few weeks may be unprecedented. In numbers alone, it raises all sort of questions, including very serious economic and diplomatic ones. And, yes, such a large influx could pose some security risks.

But, no, that viral image you saw online doesn't show an Islamic State militant among the refugee crowds.

Recently, a number of photos and videos have circulated on social media and far-right Web sites that claimed to show Islamic State militants amongst the refugees reaching Europe. One that appeared online over the past week purported to show a refugee fighting with police while carrying an "Islamic State" flag.

It spread quickly. As you can see above, even Hollywood actors shared the image.

However, when the Independent looked closer into the image, they found that the photograph had first been published over three years ago. The image showed a counter-rally that had been staged by Muslims in the German city of Bonn in response to a demonstration held by a far-right political party. While the flag may appear to be the same as the "Islamic State" flag, a number of other Islamic groups use similar ones. It's also worth noting that, back in 2012, the Islamic State, then still referred to as the Islamic State of Iraq, was a wing of al-Qaeda with relatively little support outside Iraq's borders.

So that man above is not a part of the current refugee crisis. He is probably not holding an Islamic State flag either.

This isn't the first viral image to be debunked. In early September, a Facebook user claimed to have discovered that a refugee in Europe had previously been fighting with the Islamic State. The post swiftly went viral and it continues to spread – shared almost 90,000 times at the time of writing.

Remember this guy? Posing in ISIS photos last year - now he's a "refugee"Are we suckers or what!

Posted by Peter Lee Goodchild on Thursday, September 3, 2015

However, the man in the photograph – a Syrian named Laith Al Saleh – had in fact been profiled by the Associated Press in August. It turns out he had fought in Syria's civil war, but not for the Islamic State. Instead, he had fought against them with the Free Syrian Army, a moderate group backed by the West. His home was destroyed in the fighting and he was injured in the head.

"In the first month of revolution, I was injured in the head," Saleh told the AP. "I stayed in my house about one month. After that, I came back to fight, and after a year I was wounded again, a government airplane shot a rocket at me."

So no, the refugee in that viral Facebook post is not an Islamic State militant infiltrating Europe either.

Another video that was published on a number of far right sites also presented a misleading image. This video, which spread earlier this month, claimed to show "ISIS recruits" chanting "Allahu Akbar" on a train in Europe. It has received attention from Fox News and reports of migrants shouting "Allahu Akbar" have been repeatedly raised by those who opposed to the refugees arrival in Europe.

Yet again what the video shows isn't quite so simple. For one thing, the provenance of the video is unclear – while many who share it claim it shows migrants on the train "to Germany," the train shown in the video is quite clearly a subway carriage. WorldViews was able to ascertain that this video has been online since at least 2011: It appears to have been filmed on the Paris Metro. Perhaps more importantly however, is the point that "Allahu Akbar" simply means "God is Great" in Arabic. Saying those words doesn't automatically grant you membership of the Islamic State, even if it is on a packed train in Europe.

So no, that video does not prove that the Islamic State are infiltrating Europe via refugee routes.

The refugee crisis clearly does raise some security questions. One Lebanese official recently told British prime minister David Cameron that as many as two in a hundred refugees heading to Europe could be Islamic State militants – though he also admitted this was based on a "gut feeling" rather than intelligence. A recent poll showed a surprising level of support for the Islamic State amongst Syrians, with one in five saying that the group were a positive influence in Syria. That's not quite the same as actually being willing to fight for the Islamic State, of course, but its still alarming high.

However, the "evidence" being circulated online of the Islamic State exploiting the refugee crisis to reach Europe is amazingly weak. Stripped of their original context, these images are being shared online thousands and thousands of times and used to justify the argument that Europe must forcefully refuse refugees entry. A simple online search shows that these viral stories do not show what they purport to show. Their popularity shows a widespread and willful ignorance about Europe's refugee crisis and Syria's civil war.

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