The suspect accused of fatally shooting conservative activist Charlie Kirk left behind ammunition engraved with a reference to fascism and obscure internet memes and video games, officials said Friday.

Utah Gov. Spencer Cox said inscriptions were found on at least four shell casings linked to Tyler Robinson, 22, who was arrested early Friday in connection with the killing. One engraving read, “Hey fascist! Catch! ↑ → ↓↓↓,” a seeming reference, at least in part, to a video game.

Authorities said the rounds were found with a Mauser Model 98 bolt-action rifle, fitted with a scope, that investigators recovered in a wooded area on the edge of Utah Valley University’s campus. The gun was wrapped in a dark-colored towel.

In addition to the engraving referencing fascists, Cox also referred to engravings that contained more obscure references.

On the fired casing, for instance, a message read: “notices, bulges, OWO, what’s this?”

The writing appears to be a reference to a meme about the online furry subculture and online role-play, said Jamie Cohen, an assistant professor of media studies at Queens College who researches memes. The meme has largely been used as a method of mockery and trolling, though its relevance to Kirk or the shooting is unclear.

Experts urged caution in interpreting the engravings, citing a long history of shooters using misleading or ironic messages, often mixing politics and internet culture in ways that defy easy categorization.

Cohen said he believes the messages on most of the recovered rounds were left purposely vague by a person who is “extremely online.”

The suspect may have specifically used terms that are difficult to decipher “to remain in the undercurrent of the internet,” he said.

“This type of meme is designed specifically to kind of make sure that the news can’t report on it because it comes from an extremely online approach,” he said.

Bond Benton, a Montclair State University professor who studies social media, branding, popular culture and online hate groups, said the memes come off as incoherent to most people but are embraced by those in niche online spaces.

“This sort of messaging could be sort of a wink to those people because notoriety, being the most talked about in that space, is really, really valuable to members that are of these communities,” he said.

Lindsay Hahn, a University at Buffalo associate professor who researches ideological extremism and the ways in which perpetrators of violence justify their actions, said the suspect was likely seeking fame.

His messages, she said, do not necessarily indicate a specific ideology. “But what they do indicate,” she said, “is that the shooter wanted to get a message across and therefore be talked about online.”

“It sort of seems like these messages, at the very minimum, were selected because he knew they were going to be talked about,” Hahn added.

At the Friday-morning news conference, when asked by a reporter what the messages meant, Cox said: “I will leave that up to you to interpret what those engravings mean.”

The governor said the one referring to fascists “speaks for itself.”

That particular unfired casing was also inscribed with additional symbols — an up arrow, a right arrow and three down arrows. The order of directional arrow symbols is a code used in the hit video game Helldivers 2 to summon a bomb on the player’s position.

The video game challenges players to work together as an elite team of soldiers to save Earth by pushing back invading hordes of space bugs, cyborgs and robots. Last year, it reinvigorated a long-running debate about fascism and satire.

Cox said another message read, “Oh bella ciao, bella ciao, bella ciao ciao ciao.” Cohen said this may be a reference to lyrics in a somewhat controversial Italian song that is anti-fascist in nature.

A fourth casing appeared simply to mock investigators. “If you read this, you are gay LMAO,” it read, using a well-known abbreviation for “laughing my a– off.”

It’s not clear what political perspectives Robinson held from other publicly available materials. In 2021, Robinson registered to vote with no party affiliation. Photos posted by Robinson’s mother on Facebook show him dressed up in a Halloween costume in 2017 riding on Trump’s shoulders.

Robinson joins a long list of shooting suspects from the last decade who have referenced memes, online subcultures and video games in their writings. Some have been explicit in their ideological messaging, while others have engaged in the online practice of trolling, using sarcasm and deliberately confusing references that make their ideologies hard to interpret.

The texts of many shooters who have been radicalized online are highly referential to each other.

The person who killed 51 people at a mosque in Christchurch, New Zealand, left behind writings that mixed political ideologies with memes and jokes attributing his radicalization to child video games. Another portion of the writings credited Candace Owens with his radicalization, which has widely been interpreted as satire. The gunman in a 2022 Buffalo, New York, mass shooting mixed racist memes with racist ideology, like the “great replacement theory,” and also plagiarized materials from other writings of mass shooters, making the line between his views and the views of others blurry.

In August, the suspect in a Minneapolis Catholic school shooting left a video referencing a hodgepodge of political messages and memes, from “release the files!” to skibidi toilet, that don’t appear to represent a coherent ideology.

“Oftentimes this extremely online disguise is meant to be doublespeak,” Cohen said. “It’s meant specifically for someone like me to dive into what they would call meme culture and declare them something so that they get more press. So it could just be another bait and switch for researchers who are falling into the same trap that they are designing for more viral exposure.”

Similarly, the practice of writing on ammunition and weaponry has also become a theme among shooters.

Officials say the person accused of shooting and killing a health care CEO in Manhattan appeared to have left an explicit reference — “deny,” “defend” and “depose” — to a 2010 book that was critical of the health insurance industry on the ammunition used to kill the CEO of UnitedHealth Group.

Robinson was detained Thursday night, FBI Director Kash Patel said. Cox said one of the suspect’s family members reached out to a family friend Thursday night, who then contacted the Washington County Sheriff’s Office with information that Robinson had either confessed or implied that he had carried out the shooting.

Investigators interviewed a member of the suspect’s family, who said he had become more political in recent years, according to Cox. The person said Robinson recently told them that Kirk was coming to UVU and the pair discussed how they didn’t like Kirk and the viewpoints he held.

Robinson has not yet been charged. He is expected to be charged with aggravated murder, felony discharge of a firearm causing serious bodily injury and obstruction of justice, according to a probable cause affidavit.