It is already a magnet for jihadi volunteers from Europe and beyond.
Now the militant Islamic State in Iraq and the Levant group (ISIL) has made a direct appeal to Westerners to join the wars in Syria and Iraq, with a video featuring Islamist fighters identified as Australian and British nationals.
The militants are filmed holding rifles and sitting in a row in front of the black flag of ISIL. It is thought they are in Syria.
“All you who believe, answer the call of Allah and his messenger when he calls you to what gives you life,” says one of the militants, captioned as Abu Muthanna al-Yemeni from Britain.
British media reports have identified him as medical student Nasser Muthana, 20, from the Cardiff area of Wales.
The unverified online footage will set further alarm bells ringing in the West.
Germany warned last week that an estimated 2,000 Europeans have travelled to Syria to fight alongside Islamist rebels, saying the battle-hardened jihadists are a ‘deadly danger’ when they return home.
British Prime Minister David Cameron says UK citizens and other nationals waging war with the insurgents in Iraq and Syria now pose the biggest threat to Britain’s national security.