The US believes there has been a "global surge" in foreigners fighting for Isis

There has been an "explosive growth" in foreign fighters travelling to Syria and Iraq to fight for jihadist groups such as Isis.

That's according to the US Homeland Security Committee, which says there are more foreign fighters in the two countries than at any point during the Syrian civil war.

The most common country of origin for foreigners fighting for jihadist groups is Tunisia, followed by Saudi Arabia and Jordan. There are also at least 700 Britons fighting in Iraq and Syria as well, among 4,500 westerners overall.

The committee's report states:

These fighters pose a serious threat to the United States and its allies. Armed with combat experience and extremist connections, many of them are only a plane-flight away from our shores. Even if they do not return home to plot attacks, foreign fighters have taken the lead in recruiting a new generation of terrorists and are seeking to radicalise westerners online to spread terror back home.

The full report is here.

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