Labour's Emily Thornberry has resigned from the Labour front bench over a tweet she sent during the Rochester and Strood by-election campaign.

The shadow attorney general apologised for the tweet, which showed a terraced house with three England flags, and a white van parked outside. Alongside the picture, she wrote: "Image from Rochester".

She said she had not meant to cause offence, but Labour backbencher John Mann accused her of "snobbery".

And the BBC's assistant political editor Norman Smith said on Friday that the tweet "plays to a very, very dangerous theme" for Labour, namely the concern "that they are somehow dismissive, patronising, contemptuous of their own core voters".