The exit poll has shown Labour steamrolling into No.10 with a 170-seat majority, a huge gain of 209 MPs from 2019.
Host Kay Burley was joined by Manchester’s Labour mayor Andy Burnham in the studio as the results came in.
But the pair could be heard letting out some unusual noises as they gave their shock reaction.
Mr Burnham could be seen bringing his hands together in the form of a prayer before raising his fists above his head in celebration.
Meanwhile, Ms Burley was heard repeatedly moaning as the figures appeared on a screen in the studio.
He then said: “Oh wow… that’s brilliant.”
Viewers were left stunned and confused in equal measure, with many taking to social media to question what they had heard.
On a historic night:
One said: “What was that moan about?!? Gosh, I thought something dodgy was playing in the background.”
A second wrote: “Had to turn the volume down people will think I’m watching something else.”
A third added: “I am glad this isn’t audio only.”
It comes as the same exit poll shows the Tories securing just 131 seats, 241 down from Boris Johnson’s majority five years ago.
Meanwhile, the Lib Dems are forecast to swell their seats to 61, with Nigel Farage’s Reform on course for 13 seats in an earthquake result.
Reacting to exit polls predicting a huge Labour win, Piers Morgan ribed Labour’s predicted landslide as a political “earthquake” and a “seismic night” for the UK.
But the SNP are expected to secure just 10 seats in Westminster.
Appearing on an election special of our Never Mind the Ballots show, he said: “It’s an earthquake. This is a political and social earthquake for this country, the likes of which I haven’t seen in my lifetime.
“I think first of all you have to say congratulations to Keir Starmer, who has taken the party from being completely unelectable under Jeremy Corbyn to being a party with this gigantic majority.
“Of course there’s now huge pressure on him to deliver on the faith that the electorate has shown him.
“A disaster for the Conservative Party which cannot be understated. Whichever way you look at this, it’s a seismic night.”
Analysis: Britain will wake up to political earthquake
By Kate Ferguson, Political Editor Sun on Sunday
BRITAIN will wake up tomorrow to a political earthquake.
If the exit poll is right, Labour have stormed to victory with their biggest majority in their 100 year history.
It is a jaw-dropping turnaround from the dark days of the Jeremy Corbyn era of 2019, when the party suffered their worst result in history.
The Tories look set to be decimated. The most successful political party in Europe has been reduced to just a rump of 131 MPs.
Be in no doubt – this is a nightmare for the Conservative Party. They now face the painful task of having to rebuild and choose a new leader.
But the big story of the night is Nigel Farage’s Reform party, who are expected to win a staggering 13 seats.
This political maverick has lobbed a grenade into Westminster – and he is only just getting started.
Reform is expected to win the key seat of Hartlepool – the Red Wall seat in Labour’s old heartlands which turned Tory under Boris Johnson.
Nigel, 60, the godfather of Brexit, is a charismatic leader well trained in waging war on ‘political elites’ from his days in the European Parliament.
He had run and failed to become an MP seven times before.
He has finally won on the eighth attempt – and looks set to have a dozen Reform MPs with him.
He has the potential to change the face of politics forever,
Sir Keir Starmer and the next leader of the Tories – whoever that may be – should brace themselves.