A 22-year-old man from Utah, Tyler Robinson, has been formally charged with aggravated murder after allegedly killing conservative activist Charlie Kirk. The prosecutor announced Tuesday that Robinson’s DNA was discovered on the trigger of the rifle used in the attack.

This serious charge means Robinson could potentially face the death penalty if found guilty of the crime. The incident occurred last week at Utah Valley University, located in Orem, roughly 40 miles south of Salt Lake City.

“The murder of Charlie Kirk is an American tragedy,” Utah County Attorney Jeff Gray said in announcing the charges.

Charlie Kirk was fatally shot on September 10 while engaging with students and succumbed to his injuries shortly thereafter. Prosecutors claim Robinson used a bolt-action rifle to shoot Kirk in the neck from a rooftop on campus.

A university police officer, who was observing the crowd from a high vantage point, identified the Losee Center’s roof as a possible sniper location. Evidence was quickly found there, prompting a review of surveillance footage, according to Gray.

The prosecutor, Gray, stated that Robinson’s DNA was found on the rifle’s trigger. Robinson is also accused of abandoning the weapon and clothing and asking his roommate to hide evidence.

In addition to aggravated murder, Robinson faces charges including the felony discharge of a firearm, carrying a possible life sentence, and obstructing justice, which could lead to up to 15 years in prison. Robinson was slated to appear virtually in court on Tuesday afternoon.

It was unclear whether Robinson had an attorney who could speak on his behalf, and his family has declined to comment to The Associated Press.

Robinson was arrested late Thursday near St. George, the southern Utah community where he grew up.

Investigators have spoken to Robinson’s relatives and carried out a search warrant at his family’s home in Washington, Utah, about 240 miles (390 kilometers) southwest of where the shooting happened.

Kirk, a dominant figure in conservative politics, became a confidant of President Donald Trump after founding Arizona-based Turning Point USA, one of the nation’s largest political organizations. He brought young, conservative evangelical Christians into politics. His shooting raised fears about increasing political violence in a deeply polarized United States.

While authorities say Robinson hasn’t been cooperating with investigators, they say his family and friends have been talking. Utah Gov. Spencer Cox said over the weekend that those who know Robinson say his politics shifted left in recent years and he spent a lot of time in the “dark corners of the internet.”

FBI Director Kash Patel said Monday on the Fox News Channel show “Fox & Friends” that DNA evidence has linked Robinson to a towel wrapped around a rifle found near the Utah Valley campus and a screwdriver recovered from the rooftop where the fatal shot was fired.

Before the shooting, Robinson wrote in a note that he had an opportunity to take out Kirk and was going to do it, according to Patel.

The FBI also is looking at “anyone and everyone” who was involved in a gaming chatroom on the social media platform Discord with Robinson, Patel said Tuesday during a Senate Judiciary Committee hearing in Washington. The chatroom involved “a lot more” than 20 people, he said.

“We are investigating Charlie’s assassination fully and completely and running out every lead related to any allegation of broader violence,” Patel said in response to a question about whether the Kirk shooting was being treated as part of a broader trend of violence against religious groups.

Investigators are working on finding a motive for the attack, Utah’s governor said Sunday, adding that more information may come out once Robinson appears for his initial court hearing.

Cox said Robinson’s romantic partner was transgender, which some politicians have pointed to as a sign the suspect was targeting Kirk for his anti-transgender views. But authorities have not said whether that played a role. Kirk was shot while taking a question that touched on mass shootings, gun violence and transgender people.

Utah Department of Public Safety Commissioner Beau Mason said Monday that Robinson’s partner has been cooperative. He said investigators believe Robinson acted alone during the shooting, but they also are looking at whether anyone knew of his plans beforehand.

In the days since Kirk’s assassination, Americans have found themselves facing questions about rising political violence, the deep divisions that brought the nation here and whether anything can change.

Despite calls for greater civility, some who opposed Kirk’s provocative statements about gender, race and politics criticized him after his death. Many Republicans have led the push to punish anyone they believe dishonored him, causing both public and private workers to lose their jobs or face other consequences at work.

Seewer reported from Toledo, Ohio.