David Cameron has hailed the Newark by-election result as "very good for the Conservative Party" but he said the Tories needed to "work between now and the next election" to win back voters from Ukip, who came out second in the by-election.
The PM was speaking in Bayeux, France ahead of D-Day commemoration events.
Asked how he would win back support from Nigel Farage's party he acknowledged the challenge posed by Ukip:
"The job isn't finished yet but we are on the right track, let's stick at it."
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According to local reports, the man was found by friends in their accommodation in Val Thorens resort in the Alps on Sunday morning.