Erika Kirk, the widow of rightwing activist and provocateur Charlie Kirk, said in a statement on Friday evening that her late husband’s message and mission will be “stronger, bolder, louder and greater than ever” and that her “cries will echo around the world like a battle cry”.

“I loved knowing one of his mottos was ‘never surrender’,” she said of her late husband. “We’ll never surrender.”

Charlie Kirk, the co-founder of the hard-right youth organisation Turning Point USA, died after being fatally shot while speaking at an event hosted at Utah Valley University (UVU) on Wednesday afternoon.

The event was the first in the organisation’s autumn tour of college campuses. Ms Kirk said that the campus tour will continue despite her husband’s untimely death.

“In a world filled with chaos, doubt and uncertainty, my husband’s voice will remain and it will ring out louder and more clearly than ever and his wisdom will endure,” she said.

Ms Kirk, speaking from her husband’s Turning Point USA office on Friday evening, said her husband had been killed because “he preached a message of patriotism, faith and of God’s merciful love”.

“The evildoers responsible for my husband’s assassination have no idea what they have done,” she said. “They should all know this: if you thought that my husband’s mission was powerful before, you have no idea what you just have unleashed across the country and this world.”

In what the organisation described as her address to the nation, Ms Kirk thanked law enforcement officers and those involved in finding and arresting the suspect in her husband’s murder. Tyler Robinson, a 22-year-old, was arrested on Friday in connection with the fatal shooting and is expected to be charged on Tuesday.

[ Analysis: Arrest of Charlie Kirk shooting suspect Tyler Robinson bookends latest episode of US political violenceOpens in new window ]

She also thanked JD Vance, whom she called her husband’s close friend, and Donald Trump.

“Mister president, my husband loved you and he knew that you loved him, too,” Ms Kirk said. “Your friendship was amazing.”

She talked at length about her husband’s Christian values, saying that if he would have run for office, his focus would have been to “revive the American family” and that he spent much of his time encouraging young people to find spouses and start families. She said the struggle he had been dedicated to was not political but “above all it is spiritual”.

“Spiritual warfare is palpable,” she said.

Using divisive language and at times bigoted rhetoric, Mr Kirk played a crucial role in bringing young people, especially men, into the Make America Great Again (Maga) movement. He was known for his inflammatory and discriminatory views, believed in no separation between church and state and said that Democrats “stand for everything God hates”.

He claimed the West was in a “spiritual battle” with “wokeism”, Marxism and Islam; called for a total ban on transgender healthcare; described immigration from Muslim countries as “civilisational suicide” and peddled conspiracy theories about Mr Trump’s loss in the 2020 election.

His wife used her speech to rally young people – calling out high school and college students – to continue his cause. She urged them to start or join Turning Point USA chapters at their schools.

“He wants you to make a difference and you can,” she said. “The movement is not going anywhere and it will only go stronger when you join it.”

The death of Mr Kirk – a close ally of Mr Trump – has brought renewed attention to the escalating threat of political violence in the United States. The assassination drew bipartisan condemnation from political leaders.

However, in an interview on Fox & Friends on Friday morning, the US president said “I couldn’t care less” when asked how he intended to unite the country after the shooting.

He went on: “The radicals on the right are radical because they don’t want to see crime … the radicals on the left are the problem – and they are vicious and horrible and politically savvy. They want men in women’s sports, they want transgender for everyone, they want open borders. The worst thing that happened to this country.”