The Remain campaign’s tactics have been compared to those of Nazi propaganda chief Josef Goebbels by the founder of Ukip.
Professor Alan Sked also used a speech at the London School of Economics to suggest that Prime Minister David Cameron was a lunatic.
Prof Sked said Remain “seeks to scare the voters with a Big Lie technique that Josef Goebbels himself would have been proud of”.
He went on to appear to question Mr Cameron’s mental health, stating: “We are told that Brexit- that is to say, the re-establishment of a harmless, normally self-governing, democratic Britain-would lead to war, genocide, economic collapse, terrorist infiltration, isolation and much worse.
“Not so long ago people who went around crying that the end of the world is nigh were locked up in lunatic asylums. Today they are allowed to live in Downing Street.”