The publisher of Damian McBride's memoirs is facing questions from police after tussling with a protester as the former spin doctor gave a live television interview.
Iain Dale, of Biteback Publishing, scuffled with Stuart Holmes on Brighton seafront as he tried to get the veteran campaigner's anti-nuclear banner out of shot.
Sussex Police said this evening it was "seeking to interview a man in connection with an assault".
Mr Dale, writing on his blog, said the protester - a familiar face to conference-goers for 30 years - was an "idiot" and said he had only done "what any self-respecting publisher would do" by stepping in.
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Warm and humid over the next few days with rain at times in the north.
Warm temperatures will return to parts of the UK this week, hitting highs not seen since mid-July.