By Becky Morton, Political reporter
Nigel Farage has won Reform UK’s second seat of the night, overturning a Tory majority of more than 25,000 to take Clacton.
The Reform leader beat the Tories by more than 8,000 votes in the Essex constituency.
In a speech after the result was announced, Mr Farage said it was “the first step of something that is going to stun all of you”.
It comes after former Conservative MP Lee Anderson, who defected to Reform in March, retained Ashfield in Nottinghamshire.
The BBC is now predicting Reform, which was formed in 2018 as the Brexit Party, will win four seats.
Earlier an exit poll for broadcasters forecast the party would win 13 MPs – more than many polls during the campaign had predicted.
However, the figure was highly uncertain, as the model suggested there were many places where the party only has a relatively low chance of winning.
Polling expert Sir John Curtice said Reform had benefited from a significant fall in the Conservative vote in seats the party had previously held, as well as advancing most in areas where people voted Leave in the 2016 referendum.
More than 70% of people in Ashfield and Clacton voted for Brexit.
Earlier, Mr Farage said his party was set for a “huge” general election result.
In an early sign of Reform’s success in winning over former Tory voters, the first two results of the night in north-east England – in Blyth and Ashington and in Houghton and Sunderland South – saw the party beat the Conservatives by more than 4,000 votes.
The pattern was repeated in a number of other seats, as the Tory vote share plummeted.
In a video posted on social media, Mr Farage said the two results were “more than any possible prediction or projection”.
“It’s almost unbelievable,” he said.
“It means we’re going to win seats, many, many seats I think right now across the country…
“This is going to be six million votes-plus. This folks, is huge.”
Some of the seats Reform is forecast to win could also come from Labour.
But a Labour Party source told the BBC: “Our data is suggesting Reform will not win many of the seats the exit poll suggests. They will get less than 13 seats.”
In Barnsley North, where the exit poll had forecast a 99% likelihood of Reform taking the seat, Labour held the seat with an increased majority of 7,811.
Reform’s candidate, Robert Lomas, who was disowned by the party last week for offensive comments on social media, came in second place.
In Hartlepool, another seat forecast to go to Reform, Labour also held on comfortably with a majority of 7,698.
Mr Farage has said he is aiming for Reform to become the main opposition to Labour by the time of the next election.
His surprise announcement that he was standing in the election, after previously saying he would not, saw a jump in Reform’s poll ratings.
At the same time, he took over from Richard Tice as Reform’s leader and he has played a prominent role in the party’s campaign.
The former UKIP and Brexit Party leader has stood unsuccessfully to be an MP seven times, most recently in South Thanet, Kent, in the 2015 general election, when he finished second behind the Tory candidate.
Clacton was the first constituency to elect a UKIP MP in 2014, after former Tory MP Douglas Carswell defected to the party and triggered a by-election, which he won.
In 2019 Reform’s previous incarnation, the Brexit Party, stood aside in more than 300 seats previously won by the Tories, amid concerns it could split the pro-Brexit vote.
However, this time the party contested 630 seats across England, Scotland and Wales.
Fielding an almost full slate of candidates in Great Britain posed challenges for the party.
Reform has had to disown six of them over offensive comments since nominations closed.
The party has blamed the surprise announcement of a July election, as well as claiming a company it hired to conduct background checks on would-be candidates failed to carry out vetting before the election was called.
Two Reform candidates also defected to the Conservatives over what they said was a failure of the party’s leadership to tackle the issue.
However, it was too late to remove any of these candidates so they still appeared for the party on ballot papers.