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The tweet, from an account that has now been suspended by Twitter, read: “Hiden Biden and Obama may have had Seal Team 6 killed! EXPLOSIVE: CIA Whistleblower Exposes Biden’s Alleged Role with the Deaths of Seal Team- Claims to have Documented Proof. RETWEET!!!”
The post linked to an article from blogger Kari Donovan, which further laid out the conspiracy theory and alleged that bin Laden’s body double was killed in a raid of his house in 2011 after Iran double-crossed the US as part of a deal to find the mastermind of 9/11.
After the post went viral following Mr Trump’s retweet, Robert J O'Neill, who in 2014 claimed to have been the Navy Seal who killed bin Laden, hit out at the president in a series of tweets.
“Very brave men said goodby to their kids to go kill Osama bin Laden. We were given the order by President Obama. It was not a body double. Thank you Mr President,” Mr O’Neill tweeted.
He later joked: “S**t. I just found out that I killed Osama bin Johnson. Drinks are on me, I guess…” and added: “I know who I killed, homie. Every time.”
Political pundits also reacted to the president’s retweet, and condemned his promotion of the conspiracy theory, according to Haaretz.
Co-founder of The Lincoln Project George Conway, a Republican campaign group formed to get Mr Trump out of office, tweeted: “Gosh, the president should be careful what he retweets because people might get the impression he is possibly deranged.”
While CNN anchor Jake Tapper criticised the tweet as “sheer lunacy.”
The conspiracy theory was originated by Alan Howell Parrot, who claimed in an interview with conservative personality Nick Noe at at a pro-Trump rally last weekend, that Mr Biden cut a deal with Iran to set up bin Laden’s death in Pakistan, according to The Daily Beast.
Mr Parrot claimed that Iran then double-crossed the US and switched bin Laden with a body double, which prompted Mr Biden and former US secretary of state Hillary Clinton to arrange for a Navy Seal helicopter to be shot down to keep the truth a secret.
His claims reference the attack on a helicopter in Afghanistan in 2011, which killed 25 Navy Seals and 13 others.
Mr Noe then claimed that the US attacked two of its own facilities in Benghazi, Libya, to cover up that the missile used on the helicopter was made in America.
Mr Parrot claims to have “terabytes” of evidence to prove his theory, but his version of events is not rooted in fact.
On Tuesday evening, Ms Donavan tweeted: “I have no proof that the Whistleblower's claim are true.”
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