US President Donald Trump has paid tribute to his friend Charlie Kirk at a memorial service in Arizona, calling him a martyr to America.
Mr Kirk was shot dead during a speaking event at a Utah university.
Mr Trump called Mr Kirk a great American hero and said he planned to honour Mr Kirk with the nation's highest civilian honour, the Presidential Medal of Freedom.
"Less than two weeks ago, our country was robbed of one of the brightest lights of our times," Trump told the crowd.
"None of us will ever forget Charlie Kirk, his name will live forever.
"He was a martyr to American freedom."
The service at State Farm Stadium in Glendale, Arizona, was attended by high-profile guests including Mr Trump, Vice-President JD Vance, Mr Kirk's widow, Erika, former DOGE head Elon Musk and other prominent figures from American conservative politics.
Mr Trump praised Mr Kirk for helping to convince young men to vote for him in the presidential election, saying he was instrumental in attracting the majority of males under 30.
"He did not hate his opponents, he wanted the best for them, that's where I differed from Charlie: I hate my opponents," Mr Trump said.
"He won the hearts, the minds and elections for people … he won the most important election in the history of our country."
At the end of his speech, Mr Trump embraced Mr Kirk's widow, Erika Kirk, as the American national anthem played.
Death sparks a 'revival': widow
Mr Kirk, 31, was a prominent figure within the right of American politics and was widely credited with appealing to younger Americans.
Erika Kirk said her husband's death had sparked a "revival".
"On the afternoon of September 10, I had to do the unthinkable: look at my murdered husband's body," she said.
"I felt shock, I felt awe and a level of heartache that I didn't even know existed … but there was something else too — even in death, I could see the man that I loved.
"I also saw on his lips, a faint smile — it revealed to me a great mercy in this tragedy: Charlie didn't suffer."
Ms Kirk said she forgave the man who killed her husband.
"I forgive him because it is what Christ did and what Charlie would do," she said.
"Every part of our work will become greater and it is a tremendous honour to announce that I will be taking over as CEO of Turning Point."
Top officials of the Trump administration spoke at the memorial, including Secretary of State Marco Rubio, Secretary of War Pete Hegseth and Secretary of Health and Human Services Robert F Kennedy Jnr.
Mr Rubio described Mr Kirk as being wise beyond his years.
"Charlie Kirk was bold … he actively sought to engage people he disagreed with," he said.
"He made a difference, he mattered and he will matter now more than ever.
"He had a direct impact on young men in this country and I think we will remember him for that."
He sought to push conservative messages through a mix of social media platforms.
Mr Kirk was a provocateur who at times made statements that some called racist, misogynistic, anti-immigrant and transphobic.
Thousands of mourners filled the Arizona stadium for the memorial, after lining up for hours.
Many mourners are wearing American-flag-themed clothes, shirts with pictures of Mr Kirk and MAGA merchandise.
'We are all Charlie'
Donald Trump Jnr used his speech to rally the MAGA faithful.
"We won't back down, we won't be intimidated, we will not be silenced," the president's son said.
"We are all Charlie.
"Will you surrender? Will you back down? Will you give up in fear?
"Charlie's message, like Christ's, was an invitation: if you believe in faith, if you believe in family, this movement is your home."
FBI looking into possible accomplices
Tyler Robinson, 22, has been charged with aggravated murder in relation to Mr Kirk's death.
While the memorial was ongoing, FBI Director Kash Patel announced he would be looking into the possibility of accomplices in Mr Kirk's shooting.
He said in a post on X he was committed "to ensuring the investigation into Charlie Kirk's assassination is thorough and exhaustive, pursuing every lead to its conclusion".
"We are meticulously investigating theories and questions, including the location from where the shot was taken, the possibility of accomplices, the text message confession and related conversations, Discord chats, the angle of the shot and bullet impact, how the weapon was transported, hand gestures observed as potential 'signals' near Charlie at the time of his assassination, and visitors to the alleged shooter's residence in the hours and days leading up to September 10, 2025," he wrote.
He said the FBI mourned the death of Mr Kirk and he would not rest until "justice is served".
A range of speakers, including evangelical Christians, conservative heavyweights and members of Turning Point, the organisation Mr Kirk founded, paid tribute to the right-wing activist.
Conservative commentator Tucker Carlson, who interviewed Mr Kirk multiple times on TV, paid tribute to Mr Kirk's politics and Christianity.
A video showing a combination of some of Mr Kirk's appearances and comments about him was played on the big screens at the service.
Earlier on Sunday, Prime Minister Anthony Albanese said the day was a "very sad occasion for many Americans and, indeed, people who followed Charlie Kirk right around the world".
"The memorial is being held in Arizona and our thoughts are with all those who love Charlie and his family," he told reporters in New York City.
"There's no place for political violence here or anywhere else in the world. This is a tragedy and our thoughts are with all those who will be grieving today."
