Norwegian mass killer Anders Behring Breivik raises his fist on the first day of his trial in Oslo on April 16, 2012. (Fabrizio Bensch/Reuters)

A new study by a leading British think tank suggests that not enough attention is being paid to the threat posed by right-wing violence in Europe. The study, published this week by the Royal United Services Institute, a London-based organization focused on security issues, charted a decade and a half of "lone wolf" terrorist attacks on the continent.

Its data set found that, from 2000 to 2014, "right-wing attacks caused 260 injuries and 94 fatalities, while religiously-inspired attacks killed sixteen and injured 65 people." It mapped 98 lone-actor terrorist plots in that period, "leading to 72 launched attacks of differing scope with substantial variations in impact."

The most significant episode it charts is the 2011 slaughter of 77 people by far-right Norwegian extremist Anders Behring Breivik, which accounts for a bulk of the violence noted here.

This reading, of course, does not factor in the ravages of militants connected to Islamist organizations such as the Islamic State and al-Qaeda, who have carried out deadly attacks in a number of European capitals. RUSI acknowledges that this is the primary concern of European security officials but insists that other threats also should be heeded.

"The media, and consequently public attention, is largely focused on violent Islamist extremists; while this may reflect the broader threat, it is at odds with that from lone-actor terrorism," the report says, adding that "right-wing extremists represent a substantial aspect of the lone-actor threat and must not be overlooked."

Right-wing extremists are harder to track and monitor than Islamist ones, the report claims, while Islamist lone actors are more likely to give indications of their plots to family and friends. You can read RUSI's full findings here.

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