Similar allegations were circulating on social media under the hashtags #CrisisActors and #ParklandHoax, triggering immediate calls for the accounts to be blocked.
Some claims are threatening to go mainstream because of attention from President Donald Trump's son. Some of those conspiracy theories also claim that Hogg's father Kevin, a former Federal Bureau of Investigation agent, coached the teen to speak out against Trump.
What are the conspiracy theories?.
Hogg said that while it's true his father is a former Federal Bureau of Investigation agent, it is also true that he's a Marjory Stoneman student who witnessed the shooting that took the lives of 17 of his classmates and teachers.
Speaking to CNN, Mr Hogg said it was "disturbing" that Mr Trump Jr had appeared to endorse the claim. The assailant has since been identified as 19 year-old Nikolas Cruz, who may now receive the death penalty for his heinous crimes.
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Federal law enforcement officials say Trump's posting misstates how the FBI actually works. He added that the government should focus on "evidence-based solutions" to gun violence.
He said: "I'm not a crisis actor".
"It's unbelievable to me that people are saying this, and the fact that Donald Trump Jr. liked that post is disgusting to me, but it's also false, in terms of the sense that--these people keep saying that I'm anti-Second Amendment". "I hate that people think I'm an actor, but I don't have time to care about that".
A far-right blogger shared a teenage survivor's photo with the word "EXPOSED" written in red, slamming him for being the son of a former Federal Bureau of Investigation agent. "Now, suddenly, he is a high school student in Florida???" These websites claim that David is a "crisis actor", or a pawn of gun control activists. Now skeptics are claiming the teen doesn't even live in Florida.
"But some are attacking them". In the days since the shooting, rallies, speeches, media appearances and a planned march on D.C. have all been planned and conducted by these young people who are exhausted of the political discourse that ultimately leads to another shooting. An Instagram profile reportedly belonging to David claims he's a surfer, a student film maker, and a Sun Sentinel Teenlink reporter. The company said it removed for violating its community guidelines. Kelly flagged a YouTube video where Hogg was seen in California, saying that since he was once filmed in another state, he must have been brought in during the shooting's aftermath to speak in favor of gun control.
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The video has since been removed by YouTube because it violated the platform's harassment and bullying policies, however it's since been uploaded by multiple other users across several sites.
'We are working to improve our systems moving forward'.
How are politicians responding to conspiracy theories?
There is also speculation the Russians may be fueling conspiracy theories in a bid to spread discord in America. "I am appalled at and strongly denounce his comments about the Parkland students", Kelly tweeted. "I meant no disrespect". "But grief organized for the cameras-politically orchestrated grief-strikes me as phony & inauthentic", he continued on Twitter.
After last week's deadly school shooting in Parkland, major players with a wide range of knowledge and viewpoints on the tragedy joined Michael Putney and Glenna Milberg on "This Week in South Florida".
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