Europe's REAL crisis: Terror warning as as 6,000 refugees arrive on Lesbos in just three days with no end to the human tide of misery
Europol said there could be 5,000 jihadis in the EU and the Continent is facing its biggest security crisis in ten years
It said at least 4,700 EU citizens had been recorded as fighting overseas in countries such as Syria and Iraq
Security officials fear many could have slipped back into the EU and British officials suspect 400 are in the UK