UPDATE:
Fox News acknowledges that their Twitter account was hacked.
Conspiracy theorist might call this one as plausible deniability.
From The Next Web:
Fox has found it has been made the target of a hacking campaign once again after attackers managed to compromise the Fox News Politics Twitter account and used it to spread misinformation that the president had been shot and killed.
We managed to get a screen grab of the twitter account:
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