Speaking of Scotland, the SNP candidate Humza Yousaf says the exit poll "points to a good night for the SNP".

He says there are a lot of marginal seats in Scotland, so there will be "a lot of local factors at play".

He adds: "What we have been saying is keep it calm and let's see the results as they come in."

Mr Yusuf says it looks like a "clearly good night" in Scotland, but a "disheartening result" if the Conservatives get a majority.

However, he says the the SNP will "absolutely have that mandate" to hold another independence referendum if it plays out.

Our Scotland political editor Brian Taylor will be giving his analysis on the situation there throughout the night so do check it out - he knows his stuff.

Nick Eardley
Political correspondent

If the exit polls pans out - it means one big constitutional question will be "solved’". The UK will leave the European Union under Boris Johnson.

There will be bumps along the road and negotiating a new trade deal might not be easy. But a Tory majority government will take the UK out of the EU.

If the numbers in Scotland play out, though, another constitutional clash is coming.

Senior SNP sources are telling me tonight it should force the new Tory government to concede it is up to the Scottish Parliament to decide whether it wants to hold another independence vote.

But an emboldened Conservative Party may well be tempted to say no - opposition to indyref2 has been the Scottish Tories’ main selling point since 2014.

So while Brexit might become easier to deliver - there will still be big debates over the future of the UK in the coming years.

Chris Doidge
BBC Radio Derby, political reporter

The exit poll suggests there is a 94% likelihood that Bolsover will go to the Conservatives.

Dennis Skinner has held the seat since 1970. You might know him for his fame as the man who always shouts something at Black Rod on Queen's Speech days.

Elsewhere in the county, Margaret Beckett's Derby South seat is too close to call while Derby North is likely to go Conservative, but still quite close.

As #CorbynOut begins trending on Twitter, Siobhan McDonagh, Labour's candidate for Mitcham and Morden, knows who she blames.

And our correspondents tell us about other reaction they've been hearing...

The Brexit Party is not expected to win any seats tonight but party leader Nigel Farage tells the BBC's Andrew Neil: "If we get Brexit, we've done a good job."

However, he adds that if Boris Johnson's Brexit deal passes unamended "I can't bring myself to support it."

He thinks it'll result in a closer relationship with the EU going forward than he'd like.

"My purpose was to try to get right kind of Brexit - if we get half a loaf out of it - that is what we achieved," he says.

Asked if he will now step down from politics, he says: "Let's see where we are in six months - I may have to throw my hat back into the ring."

On his own vote, he says he couldn't bring himself to support the Conservatives so he spoiled his ballot paper.

"How I voted under this system is pretty irrelevant," he adds attacking first-past-the-post.

Image source, Getty Images

This is a piece you want to bookmark. Our colleague Emma Harrison will be keeping a running list of the key points, the at-a-glance, 100% must-knows as the night goes on.

Check it out...

We're starting to unpick some of the key points from our live exit poll forecast.

Our digital journalist Joey D'Urso points out one of the most interesting predictions - about Lib Dem leader Jo Swinson.

However, it must be said that the prediction for Scotland is potentially less reliable than for other parts of the UK - the exit poll needs a bit more of a health warning there.

But still, very interesting nonetheless.

Nick Eardley
Political correspondent

This result would deliver a striking verdict on the two men at the heart of this election.

Boris Johnson will be emboldened and vindicated - a hero even for those Tories who were sceptical about his Brexit approach. Frankly, in raw political terms, his strategy will have paid off.

For Jeremy Corbyn, this would be a crushing blow. His strategy of neutrality on Brexit has failed - as has his plan to try and move the focus onto other issues in this campaign by promising massive spending.

I’ve been speaking to Labour candidates who say it’s hard to see how Mr Corbyn can survive - and you can expect considerable speculation over the next few hours about who might replace him.

This is the first reaction from the Lib Dems now on the BBC News election special. Candidate Christine Jardine says everybody is looking closely at the exit poll to "see if we can read a bit more into it".

She says such polls are good at predicting the national picture but not so good locally - especially in Scotland, where she is standing. That's also where her leader Jo Swinson is standing and could be vulnerable.

"The poll doesn't reflect what we have been seeing on the ground in Scotland," she says.

"Only two or three months ago we had a by-election in Shetland where the SNP threw everything at it... yet they didn't win and the Lib Dems held that seat.

"Tonight all feels a bit of a surprise."

Image source, Nigel Roddis/PA Wire

We should be getting our first result pretty soon, and it'll be from somewhere in the North East.

Ritula Shah is at the count in Blyth Leisure Centre, where volunteers are racing to get through their ballot boxes ahead of their rivals down the road in Sunderland.

"There's people running past me with more boxes full of votes as we speak," she says.

"They've got an extraordinary system here - the vans pull up outside, there are large numbers of young, very athletic looking runners, who sprint down the corridor with the boxes.

"They are running round and determined to get this done within about 45 minutes or so."

Read our feature about the famous Newcastle-Sunderland race here.

Andrew Marr
Presenter, The Andrew Marr Show

If it is true - and it is only an exit poll - that the so-called "red wall" has fallen, that changes the nature of the Conservative Party.

There will be lots and lots of new Tory MPs representing areas that depend on public services and like high spending on them.

It is also going to give Boris Johnson more freedom when it comes to Brexit.

And with all of those trade offs next year with the EU, he will be able to give more than he was intending to.

It probably means a slightly softer Brexit, which will leave Nigel Farage cross and the pro-Brexit ERG group cross.

But it has freed the PM to show us what the real Boris Johnson is like.

BBC News Channel

The chief executive of pollsters Ipsos Mori, Ben Page, says: "It is very unlikely the exit poll is wrong enough to mean the Conservatives have not got a large majority.

"If the poll is correct we will see dozens of Labour seats going to the Conservatives and you may even see places like Bolsover going to the Tories.

"In Wales, the Conservatives look to be making gains as well as the Midlands.

"This is a recasting of British politics around the Brexit vote.

"And that is what this election has been about."

Remember that after the 2017 election Theresa May was forced to seek support from the DUP to have a functioning majority.

That relationship broke down when Boris Johnson brought back a Brexit deal the DUP found unacceptable.

Green Party candidate Caroline Lucas, who previously held the party's only seat in Parliament, tweets her take on the exit poll result.

The poll predicts her party will win one seat again this time.

Here's a handy tool to explore the general election 2019 exit poll across every constituency in Great Britain.

Laura Kuenssberg
BBC political editor

The issue of Brexit doesn't explain as bad a performance as this for the Labour Party - even if that's what John McDonnell and Barry Gardiner say.

Labour candidates have said to us again and again - we have a problem with Brexit but also the leadership.

What they have found on the doorstep is that traditional Labour voters were reluctant to back Jeremy Corbyn - they had a problem with anti-Semitism and some issues with the manifesto.

I don't think the Labour Party as a whole will buy the argument that tonight's result is just about the EU.

Katya Adler
Europe Editor

All the leaders of the other EU are together tonight - they're at an EU summit.

As the poll came out they were supposed to be discussing Libya, but I'm told everyone was on their phone checking the result.

If this result is confirmed this is what the EU wants to see - it is not about Labour or the Conservatives, but about having a clear path forward and ending the uncertainty.

And there's a hope in EU circles that if this is a big win for Boris Johnson it could mean he can ignore the more extreme Brexiteers in his party and have a closer relationship with the EU.

First bit of reaction from the Brexit Party. You'll remember they didn't run in seats the Conservatives won in 2017 and made repeated appeals to Labour Leave voters.