The revelation was presented to Trump supporters in Wilkes-Barre, Pennsylvania, as a bombshell that “just came out a little while ago”

With a flourish Donald Trump brandished a sheet of paper in front of thousands of fervent supporters and fed them misinformation straight from the Kremlin’s propaganda network.

He read them a leaked email that he claimed showed that Sidney Blumenthal, a long-time confidant of Hillary Clinton and favourite target of right-wing conspiracy theorists, had secretly admitted that the deadly attack on the US embassy in Benghazi in 2012 was “preventable” — while the crowd booed and chanted “Lock her up!”

New emails leaked by Wikileaks also confirmed “what those of us here today have known all along,” Mr Trump said at a separate rally last night. “Hillary Clinton is the vessel for a corrupt global establishment that is raiding our country and surrendering our sovereignty.”