This article was produced for ProPublica’s Local Reporting Network in partnership with Wisconsin Watch. Sign up for Dispatches to get stories like this one as soon as they are published.
Moments before 15-year-old Natalie Rupnow opened fire inside her Madison, Wisconsin, school, killing two people and herself last month, a social media account believed to be hers posted a photograph on X showing someone sitting in a bathroom stall and flashing a hand gesture that has become a symbol for white supremacy.
As news about the shooting broke, another X user responded: “Livestream it.”
Extremism researchers now believe that second account belonged to 17-year-old Solomon Henderson, who police say walked into his high school cafeteria in Nashville, Tennessee, on Wednesday and fired 10 shots, killing one classmate and then himself. Archives of another X account linked to him show that he posted a similar photo to Rupnow’s in his final moments.
While there isn’t any evidence that Rupnow and Henderson plotted their attacks together, extremism researchers who have tracked their social media activity told Wisconsin Watch and ProPublica that the two teenagers were active in the same online networks that glorify mass shooters, even crossing paths. Across various social media platforms, the networks trade hateful memes alongside terrorist literature, exchange tips on how to effectively commit attacks and encourage one another to carry out their own.
The researchers had been tracking these networks for months as part of work looking into growing online extremist networks that have proliferated across gaming, chatting and social media platforms and that they believe are radicalizing young people to commit mass shootings and other violence.
The researchers’ analysis found only a few instances in which Rupnow and Henderson appeared to interact directly. But in the hours, days and weeks that followed the Madison shooting, Henderson appears to have become fixated on Rupnow. He boasted on X that Rupnow and him were “mutuals,” a common internet term for following each other, and shared another post that said, “i used to be mutuals with someone who is now a real school shooter ;-).”
Credit:
Obtained by Wisconsin Watch and ProPublica. Screenshots by ProPublica. Blurred by ProPublica.
The researchers, who have collaborated with counterterrorism organizations, academics and law enforcement to prevent violence by tracking how extremist networks radicalize youth online, agreed to share information as long as they weren’t named out of concerns for their physical safety. The news outlets vetted their credentials with several experts in the field.
It’s impossible to know with complete certainty that online accounts belong to particular people without specialized access to devices and accounts from law enforcement. The Metropolitan Nashville Police Department has acknowledged the existence of two documents they believe Henderson created, both of which contain details about his social media accounts. Other researchers and groups — including the Anti-Defamation League, Canadian extremism expert Marc-André Argentino and SITE Intelligence Group — have also determined these likely belong to Henderson.
The extremism researchers linked accounts to Rupnow, who went by Samantha, by tracing her activity across multiple social media profiles that revealed common biographical details, including personal acquaintances and that she lived in Wisconsin. On the bathroom post, one person the account regularly interacted with referred to Rupnow by her nickname, “Sam.” Wisconsin Watch and ProPublica were able to verify the social media posts and the connections between the accounts by retracing the researchers’ steps through archived social media accounts and screenshots.
On Thursday, ABC News cited law enforcement sources in reporting that a social media account connected to Henderson may have been in contact with Rupnow’s social media account. The information reviewed by Wisconsin Watch and ProPublica details their suspected connections and interactions. Nearly all of the accounts that researchers have linked to Rupnow and Henderson have now been suspended.
A Madison Police Department spokesperson said the agency knows Rupnow “was very active on social media” and it is “just starting” to receive and review documents from tech companies. The Nashville police said they had nothing further to add beyond their previous statements.
Rubi Patricia Vergara, 14, and Erin West, 42, were killed at Abundant Life Christian School in Madison. Josselin Corea Escalante, 16, died at Antioch High School in Nashville. Both attackers also killed themselves.
Rupnow and Henderson each had multiple X accounts, the extremism researchers told Wisconsin Watch and ProPublica. At the time of her attack, Rupnow followed just 13 other users. Two of those accounts have been linked to Henderson.
In November, Rupnow shared a post from Henderson, which appeared to wish a happy Veterans Day to the man who killed more than a dozen people at University of Texas at Austin in 1966.
After the Madison attack, someone wrote to Henderson and others on X, saying that one of their “buddies” may have “shot up a school.” Henderson told another user, “I barely know her,” and said he had never exchanged private messages with her. Later, in a 51-page screed that Nashville police are examining, he emulated and praised several past attackers including Rupnow and said, “I have connections with some of them only loosely via online messaging platforms.”
However the two teens entered this online subculture, their writings reveal despair about their personal lives and the world around them and expressed violent, hateful views.
After the Madison shooting, a separate social media user noted their association and tweeted at the FBI, accusing Henderson and others of having prior warning. They “need to be locked up,” the poster said, “no questions asked.”
The FBI declined to comment.
