The Guardian has the full story:
"Accusations range from political activists putting pressure on people to mark their party's box on the postal vote form, to phantom voters being registered by candidates and their supporters to farm votes. The problems have emerged before most postal votes have been returned."
The Graun' lists some areas:
"In London the Metropolitan police have received 28 complaints across 12 boroughs and launched five investigations – one in Ealing and four in Tower Hamlets, which has a history of problems with electoral fraud"
"West Yorkshire police have received 19 complaints and launched five investigations across Bradford and Calderdale, where two arrests have been made."
A little analysis of the areas listed reveals an .. ahem .. interesting correlation. A correlation that the Guardian, bless 'em, appears to have somehow totally fucking missed.
'Ealing' - Ealing Southall - is a Labour seat;
'Tower Hamlets' could be one of two seats: Poplar & Canning, which is Labour seat, or Bethnal Green which Labour are just desperately keen to pinch back from Gorgeous George Galloway;
'Bradford'? Well, that could be one or more of three: Bradford North, which is Labour, Bradford West, which is .. err .. Labour and Bradford South which is .. yeah .. Labour;
And as for 'Calderdale' - Calder Valley - you may be astonished to learn this, but that seat is held by ... Labour.
Can you see how these seats might have come to be held by Labour? Can you see how they might manage to retain them in Thursday's election? Does, in short, a pattern begin to emerge?
Of course it fucking does.