Here's what those who carried out 28 attacks in the US have in common: Secret Service

 A secret Service report details the common elements of 28 mass shootings in 2017: 100% were committed by males ages 15-66; 79% sent threatening or concerning communications and 64% experienced mental health symptoms prior to attack. Know the warning signs. 

Seventy-nine percent of those who conducted a mass attack in the U.S. last year had previously engaged in threatening or concerning communications, with one-third…

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