Kirk, the founder of the conservative youth activist organization Turning Point USA, was fatally shot during an event at Utah Valley University on Wednesday, President Donald Trump said.
Utah Gov. Spencer Cox called the fatal shooting a "political assassination."
READ MORE: Charlie Kirk fatally shot while visiting Utah university in 'political assassination,' governor says
Charlie Kirk fatally shot while visiting Utah university
Kirk held no official position in the Republican Party or the Trump administration, but he was a strong supporter.
Eyewitness News spoke to a retired FBI agent, who issued a warning to political commentators.
Threats against politicians have been common historically, and they remain common, but experts say Wednesday's shooting is different because Kirk held no elected position, had no legislative power and no power to sign an executive order. He was an activist and a commentator.
The shooting comes as the FBI has been warning for years that we are in an era of heightened threats. Just last year, when then-candidate Trump was shot in Pennsylvania, the FBI sent out a release that it had seen "an increase in threats of violence targeting government officials, houses of worship, schools and medical facilities," just to name a few.
Former FBI Los Angeles Field Office agent Bobby Chacon says if he were advising an elected official or political activist right now, he would not want them speaking in open, outdoor venues.
"If my job was to keep you 100% safe -- that would be my advice. And I hate to say that," Chacon said. "Certainly not an open forum like where we saw Trump shot in Pennsylvania or Charlie Kirk killed today."
Former LAPD deputy chief discusses security measures at political events
"Obviously, it was a political assassination. It looked like it was from a high-powered long gun, probably from a position of height in a sniper position," said Michael Downing, a retired deputy chief with the Los Angeles Police Department and the chief security officer for Oakview Group. "In an environment like that, you have an open area. You have a security team that's around you, inside a bike rail, but the rest of the campus is very porous. You have high ground all around you, and as I understand it, even if it was a ticketed event, they weren't checking tickets, so it's a really difficult event to secure."
Like many, Downing worries about where we go from here, not only as far as security is concerned for these kinds of events, but for the nation as a whole.
"I know this isn't a national security event, but it is a political event. The country is very divided right now, and violence in politics is the poison that corrodes democracy, and no matter who is the target, or what ideology they represent, it's something we have to really concern ourselves with," Downing said. "Security professionals need to step up and make sure they go back to the basics, they understand what threat assessments are, they know how to do them, first of all, and then they know how to execute on those threat assessments to make sure these types of venues are absolutely safe."
Just last week, House Speaker Mike Johnson said U.S. Capitol police looked into 9,000 threats made against members of Congress. So far this year, there's already been 14,000 threats that Capitol police have had to look into.
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