Analysts with the ADL Center on Extremism "have located a manifesto and social media accounts believed to belong to the shooter, where he shared a range of incel, accelerationist, white supremacist, antisemitic & anti-Black content," the organization wrote in a Wednesday post on X (formerly Twitter ).

A teenager opened fire at Antioch High School Wednesday killing a student and leaving a mourning community that has already seen two mass shooting incidents in recent years.