The man, who bore a striking resemblance to Mr Corbyn, arrived at the stage door of the studio in Salford and claimed to be the politician.
ITV News political editor Robert Peston tweeted a picture of the man and wrote: “This bloke turned up at stage door for the debate.”
And BBC Breakfast reporter Monika Plaha shared a video of the lookalike marching up to the ITV studios with an entourage of people.
One person commented that the impersonator is “pretending to be the Leader of the Opposition. As, indeed, is Jeremy Corbyn”.
Another commented that the “likeness is astonishing”.
In 90 seconds: The ITV Leaders’ Debate
Both Mr Corbyn and Theresa May have come under fire for not taking part in Thursday evening’s debate.
The Prime Minister said she would not be involved in any TV debates and Mr Corbyn said he would not take part unless she was present.
Instead, the leaders of the Lib Dems, Ukip, Green Party, Plaid Cymru and the SNP will face off for the two-hour debate chaired by broadcaster Julie Etchingham.
Debate: Caroline Lucas, Tim Farron, Leanne Wood, Paul Nuttall, Nicola Sturgeon and presenter Julie Etchingham (Rex Features)
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