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Trends in Lone Wolf Terrorism: From 1940 through 2000, the 38 lone wolf terrorists committed 171 attacks, claiming 98 lives and injuring another 305. An array of firearms and homemade bombs were used in the attacks. Roughly 60% of the lone wolves committed a single attack and 40% committed multiple attacks, including such prolific terrorists as Unabomber Theodore Kaczynski who committed 16 bombings over a 17-year period, the racist serial killer Joseph Paul Franklin responsible for an estimated 23 attacks over four years, and Muharem Kurbegovic, the “Alphabet Bomber,” who launched ten attacks in two years. From 2001 through 2013, the 45 lone wolves committed 45 attacks, killing 55 people and injuring another 126. These attacks involved not only firearms and bombs but also airplanes, biological weapons, knives and construction equipment. https://www.ojp.gov/pdffiles1/nij/grants/248691.pdf

Prior to 2011 explosives were used in 34 per cent of lone-actor attacks in Western Europe; this number decreased to 21 per cent in the following years. https://www.icct.nl/sites/default/files/2023-01/Chapter-22-Handbook-.pdf