Damian McBride has insisted that Labou leader Ed Miliband and shadow Chancellor Ed Balls knew nothing of his toxic briefings against other cabinet members.
He told ITV News' Deputy Political Editor Chris Ship that it "would have taken something of a criminologist" to trace some of the stories he was planting in the press back to him.
He also alleges that Downing Street advisers in "Miliband's camp" briefed against Balls during Gordon Brown's last days as prime minister.
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