GETTY Passports solicited by Islamic State have been found in Greek refugee camps

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Europol officials carried out a long running investigation followed by a series of raids and unearthed the counterfeit documents, leading to fears that terrorists are sneaking into the EU among refugees. The international investigation stretched around the world, with police monitoring events in Syria, Iraq, Greece and Austria in an attempt to find out where the documents were being used to breach borders.

At least two of the perpetrators of November's terror attacks in Paris re-entered Europe from Syria posing as refugees and travelling on false Syrian documents. Italian newspaper La Stampa claims ISIS-inspired terrorists are currently trying to make their way to Austria, via Greece, giving themselves a European base from which to carry out deadly attacks.

GETTY There are fears that ISIS terrorists have infiltrated Europe's refugee camps

La Stampa said: “In particular they have identified fake passports in the refugee camps in Greece that were destined to supposed members of ISIS.” Some 58,000 migrants have arrived in Greece since the closure of the Western Balkan route – a busy channel used by refugees to escape the turmoil in their Middle Eastern homelands and get to Europe.

Government figures showed 261 migrants or refugees arrived on Greek islands in the 24 hours from Thursday morning to Friday morning, which marks and increase compared to recent figures, which show between 12 and 150 people coming ashore. The International Organisation for Migration says that 266,026 migrants and refugees entered Europe by sea to August 17 – more than 162,015 landed in Greece. In July, Europol’s European Migrant Smuggling Centre (EMSC) helped the Austrian and Hungarian authorities smash an Austrian-based organised crime group involved in migrant smuggling.

Migrants clash with police across Europe Wed, February 15, 2017 Migrants clash with each other in over crowded camps across Europe. Play slideshow EPA 1 of 107 Moroccan Police look at immigrants trying to jump the six-meter-high fence in Ceuta, Spanish enclave on the north of Africa, 09 December 2016.