Shadow home secretary Yvette Cooper has accused Gordon Brown's former aide Damian McBride of being "out of control".
Cooper, whose husband Ed Balls was a key Brownite, told Sky News' Murnaghan programme: "I think this is ... about a kind of politics that really is appalling, that we should never go back to.
"It is something that happened some years ago, but I think it's a sign of how much the Labour Party has changed, the very different climate, the very different way in which Ed Miliband is managing things and operating things now, that's a good thing.
"We don't want to go back to the navel gazing of the past."
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One story dominates Thursday's front pages with some newspapers printing emotive pleas to voters to keep the United Kingdom as one.
After a mild start temperatures should pick up, with the south of England seeing highs of 26C.
In Edinburgh tonight you can hear it and feel it. The buzz, the banter of the day and the thrilling sense something big is coming tomorrow.