Tyler Robinson, 22, shared detailed messages on the chat platform Discord about weapons, movement and the aftermath of the attack that killed conservative activist Charlie Kirk, authorities said, as investigators released new information about the suspected shooter’s online footprint and the inscriptions on bullets used in the killing.

Robinson was arrested Thursday after police say he opened fire while Kirk, 31, spoke at an event at Utah Valley University in Orem on Wednesday. Officials said Robinson posted messages describing retrieving a rifle from a drop point, wrapping the weapon in a towel and stashing it in a bush, then using a scope and changing clothes before the attack.

Utah Governor Spencer Cox and other officials said investigators found engraved messages on spent and unfired casings recovered at the scene. One spent round was engraved with the phrase, "Notices bulges OWO, what's this?"—a meme investigators said is used online to mock furries and transgender people. Another bore the words "Hey Fascists! Catch" accompanied by arrow symbols that investigators said could reference anti-fascist iconography. A third carried the line from the Italian partisan song "Bella Ciao," and an unfired casing was engraved with the taunt, "If you read this you are gay LMAO," officials said.

Authorities said the inscriptions and the Discord posts were part of the evidence that prompted a rapid manhunt. Robinson was detained around 10 p.m. Thursday after his father and a minister in southern Utah turned him in to police following the release of images of a person of interest. FBI Director Kash Patel described the capture as "historic," saying the bureau and partner agencies ended the search within 33 hours.

Police said Robinson arrived on the UVU campus driving a gray Dodge Challenger and was wearing a plain maroon T-shirt, light-colored shorts, a black hat with a white logo and light-colored shoes when he allegedly opened fire. Kirk, a father of two and a well-known conservative commentator who frequently debated students on college campuses, collapsed after being struck, authorities said.

Investigators said Robinson, who lives in a six-bedroom home in Washington, Utah, about 260 miles south of Orem, had become more politically engaged in recent years. Governor Cox said family members had discussed Kirk’s appearance at UVU and that Robinson had expressed dislike of Kirk’s viewpoints. In one conversation with a relative, Robinson allegedly said Kirk "was full of hate and spreading hate," Cox said.

Law enforcement officials emphasized that the investigation is ongoing and described the collected digital and physical evidence. Police accounts of Discord messages and the bullet engravings have been provided to prosecutors as officials weigh potential charges. Prosecutors have not released formal charging documents as of the latest statements from authorities.

The killing has drawn swift national attention and political reaction. Former President Donald Trump, who has frequently defended conservative activists and commentators, called for Robinson to receive the death penalty in connection with Kirk’s death, describing Kirk as "the finest person." Officials said they would not comment on potential sentencing pending the outcome of prosecutors’ decisions and court proceedings.

Robinson’s family social media profiles show images of vacations and everyday life, including posts celebrating his college acceptance, officials said. Police have not publicly described a motive beyond the material investigators recovered and the statements attributed to Robinson and family members. Authorities cautioned against speculation while the investigation and any subsequent prosecution proceed.

Discord, the platform cited in investigators’ summaries, is used for group chats and voice communications among users with shared interests, including gaming and hobby communities. Officials said the platform’s messages helped map Robinson’s movements before and after the shooting and provided context about his online activity. The Utah law enforcement agencies are coordinating with federal partners on the probe.

As the case moves into the prosecutorial phase, investigators said they will continue to review digital devices, social media posts and additional forensic evidence. Officials urged anyone with further information connected to the UVU shooting to come forward to assist the ongoing inquiry.