Riley Gaines mourned the assassination ofCharlie Kirk, who she called "a friend and mentor," in a lengthy, emotional video in which she condemned the act of political violence against the popular conservative activist.Gaines, the host of OutKicks"Gaines for Girls" podcast and a 12-time NCAA All-American swimmer, shared her thoughts in a video posted by OutKick Thursday. The video came after the killing of Kirk, who was fatally struck by a single bullet during a speaking event on the campus of Utah Valley University on Wednesday."Ive lost a friend, a mentor, the person I go to,"Gaines began. "The intellectual mind and genius that is Charlie Kirk, the generational talent, I truthfully believe that his impact alone as one person and what hes been able to do through Turning Point, which Im a very very proud contributor of, I talk about it on this show all the time, what hes been able to do is transform a nation, revive a culture. A culture of young people, people just like me."CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COMGaines, who sat alongside Kirk for the "American Comeback Tour" event atSan Francisco State University in May, mourned for Kirks wife and two young children."I lost a friend and a mentor, Erika lost her husband, I cant help but think about her. This is one of the most kind and compassionate women you can possibly imagine. This was her greatest fear, I mean we had talked about it. This is her greatest fear, I wont go into the details there, two children lost their father. They will be haunted forever by the videos that cant be scrubbed from social media."CLICK HERE TO WATCH RILEY GAINES FULL TRIBUTE TO CHARLIE KIRKLike many who have spoken out on social media following the assassination, Gaines called the lack of tolerance for open discourse in the U.S.TIMELINE OF CHARLIE KIRK ASSASSINATION"This nation has lost the best and most effective, most influential activist its ever had and Im not even just talking about a conservative activist. Im talking about on both sides," she said, later adding, "We dont have to live like this. We shouldnt have to live like this, in fear of speaking the truth raw and unfiltered."Gaines said that despite the tragedy of Kirks killing, her shared faith values with Kirk have kept her "grounded.""Im so grateful, thats really like the thing keeping me is any amount of grounded is knowing that Charlie knew Jesus. Knowing that he was a man who fought for the hope and the promise of eternal life, nothing of this world mattered to Charlie. Of course he loved his family, of course he loved this nation, he loved the truth, but he was fighting for eternal life and so my message to everyone listening is this: Is to take up the cross, is to live a life like Charlie Kirk did, to live a Christ-like life."Gaines went on to commend Kirk for his willingness "to go into the belly of the beast" and speak out about the values he cared about.Police confirmed Friday that a suspect in Kirks killing was arrested. He was identified as Tyler Robinson, a 22-year-old Utah resident. Utah Gov. Spencer Cox stated that a family member of Robinsons contacted a family friend who then reached out to the Washington County Sheriffs Office "with information that Robinson had confessed to them or implied that he had committed the incident."Follow Fox News Digitals sports coverage on X, and subscribe to the Fox News Sports Huddle newsletter.