A new U.S. Secret Service report on mass shootings says last year's shooting in Dayton was preventable.
The report found several red flags before Connor Betts killed nine people and injured 32 more, including comments that disturbed his high school classmates and a rap sheet of violent crimes. The Secret Service say many of the suspects in mass attacks in the U.S. last year had experienced stressors, like losing their job, or had struggled with substance abuse or mental health symptoms.
The report examined 34 attacks that killed or injured three or more people. Investigators found nearly half of the attackers had used guns they possessed illegally, and about two-thirds had exhibited behavior that was concerning to others.