Religious terrorism grows in the European Union

The brutal attacks in Paris on Friday have left Europe and the world asking the question of what can be done to prevent further violence.

France, in particular, has been targeted this year, first with the deaths of 12 people at the offices of the satirical Charlie Hebdo magazine in January. One of the perpetrators of that attack was later killed by police at a kosher supermarket after killing four more. In June, a manager was beheaded by an employee at a chemical plant in Lyon.

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But it's not the first time France has handled dangerous terrorists. Between left-wing radicals and separatist movements, European authorities have battled terrorists — foreign factions and homegrown — for decades.

French and European authorities made 238 arrests in 2014 on terrorism-related charges, according to data from Europol, the European Union's central police. That's the most in the economic bloc, followed by Spain and the United Kingdom, which arrested 145 individuals and 132 individuals, respectively.

While terrorist attacks by separatists — think dissident republican groups in Northern Ireland — still make the most attacks in the EU, their numbers are decreasing. It's religiously inspired attacks that worry authorities most, according to Europol's 2015 report.

Law enforcement recognizes that and is putting more resources toward fighting religious fanatics. For the first time in 2013, arrests for religiously inspired terrorism outnumbered those of separatists.

Still, terrorism in Europe is nothing like it was in the heyday of the Irish Republican Army and Germany's Baader-Meinhof group. Attacks across Western Europe have dropped significantly in the past 40 years, according to data collected by the Global Terrorism Database.

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