Chris Mason,Political editor, @ChrisMasonBBC
Sir Keir Starmer has been accused of carrying out a purge of left-wing candidates ahead of the selection deadline for the general election.
The Labour leader denies this but some in his party don’t believe him.
“This factional, vindictive behaviour is designed to humiliate socialist candidates as well as block them.”
These are the words of Beth Winter – who was, until Wednesday, a Labour MP and is standing down.
Labour want to talk about anti-social behaviour today, but they are themselves having a very public slanging match that is not exactly neighbourly.
Let me give you four names: Jeremy Corbyn, Diane Abbott, Faiza Shaheen and Lloyd Russell-Moyle.
Ms Winter is furious at what is happening to Ms Abbott and Ms Shaheen.
Mr Corbyn and Mr Russell Moyle won’t be running as Labour candidates, and right now it looks like Ms Abbott and Ms Shaheen won’t be either.
Labour make the argument that each of their cases are different, and there is some truth in that.
It is also true to say they are all prominent left-wing voices, at just the moment something else is going on.
Indulge me with a bit of imagery for a second.
If you were to look through a pair of political binoculars right now, and point them towards the sky, you would see parachutes descending from above.
Clinging to the ropes and smiling, a collection of Labour figures likely to be Starmer loyalists.
Two examples: there is Josh Simons, who has run what is seen as the Starmerite Labour Together organisation, and will be Labour’s candidate in near Wigan.
And there is a former adviser to Rachel Reeves, Heather Iqbal, in Dewsbury and Batley in West Yorkshire.
So the loyalists get the thumbs up, the potential troublemakers do not, argue those on the Left.
To an extent, twas ever thus – leaders of all parties try to ensure they build a party in their own image.
And Sir Keir will worry that were he to manage a majority but only a narrow one, he could be beholden to Labour’s left wing.
But what gives this row crackle is Mr Corbyn and Ms Abbott in particular are cause celebres – because after the left wing’s recent dominance in the party, they have a prominence they wouldn’t otherwise have had.
“It’s complicated” a senior Labour figure close to the leadership tells me about the Diane Abbott row.
It sounds like a relationship status update on someone’s social media profile, but actually amounts to an understatement of the political relationship between Ms Abbott and the Labour leadership.
She reckons she has been barred from standing.
The party centrally says that she hasn’t.
This is how both these things could be true: if she does decide to stand, the party’s National Executive Committee would need to approve her, and they may decide not to.
There had been a hope from a lot of Labour folk that having readmitted her into the parliamentary party this week, just before Parliament dissolved, she would decide to retire, would be garlanded with public praise by senior Labour figures from Sir Keir down, and that would be the end of things.
It hasn’t exactly turned out like that.
Now add in that that those close to Ms Shaheen have told the BBC that she has “instructed a lawyer and is challenging the decision against her”.
The noise isn’t dying down.
And now Sir Keir’s deputy Angela Rayner has added to it, telling ITV: “I don’t see any reason why Diane Abbott can’t stand as a Labour MP.”
Ms Rayner goes on to say that she does not believe Sir Keir is behaving in a “factional way” – and she does not believe a purge of left-wingers is being carried out.
But her intervention will add fuel to an increasingly combustible row.
All this does mean Sir Keir can say this is a further illustration of how the party has changed.
Recent Conservative voters may be reassured that voices on the left of the Labour Party, for whatever reasons, are being squashed.
But it also means whatever else they want to talk about gets drowned out.
And it means the Conservatives can – and are – asking if Sir Keir can’t deal quickly and quietly with Diane Abbott, how would he stand up to the Russian President Vladimir Putin?
The election campaign is stepping up a gear.
A full list of candidates for all constituencies will be available on the BBC News website once nominations are closed.
