The entire European Union is under threat as almost all its governments back the US-led coalition in Syria, Reuters.
The EU police agency Europol warned on Friday Islamic State (IS) is likely to launch more attacks in Europe, with several dozen militants already in Europe.
In a report on the threat the Islamist group poses to the 28-nation bloc, Europol said the most probable forms of attack would be those used in recent years, from the mass shootings and suicide bombings seen in Paris and Brussels to stabbings and other assaults by radicals acting alone.
The report warnes that IS was likely to infiltrate Syrian refugee communities in Europe in an effort to inflame hostility to immigrants that has shaken many EU governments.
"If IS is defeated or severely weakened in Syria/Iraq by the coalition forces, there may be an increased rate in the return of foreign fighters and their families from the region to the EU or to other conflict areas," Europol said in a statement.
Europol Director Rob Wainwright said the bloc had boosted up the security cooperation between member states in the wake of IS attacks in the last couple of years, that allows more plots to be foiled.
"Nevertheless," he said, "Today's report shows that the threat is still high and includes diverse components which can be only tackled by even better collaboration."