Jean-Marie Le Pen, the former leader of France's far-right National Front (FN) party, was convicted on Wednesday of denying crimes against humanity for repeating that the Nazi gas chambers are a "detail" of World War II.

The 87-year-old, who was succeeded by his daughter, Marine, as FN head in 2011, was ordered to pay a 30,000 euros ($34,000) fine plus damages to three charities which brought the case.

The judges also ordered that verdict be published in three newspapers.

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The FN founder was convicted of the same offence in 2012 for claiming that the Nazi occupation of France was not "particularly inhumane".

Decades ago, Le Pen was convicted for saying the gas chambers were "a detail of the history of the Second World War".

He repeated the remark in April last year, telling France's BFMTV news channel: "Gas chambers were a detail of the war, unless we accept that the war is a detail of the gas chambers."

Le Pen was expelled from FN last year in a bid to shed the party's anti-Semitic reputation and bolster Marine's prospects in a presidential election bid.

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Source: Agencies