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Around 600 Holocaust survivors and veterans attended the service.

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The Queen hosted a reception for Holocaust survivors at St James's Palace before attending the Westminster ceremony, where she lit a candle.

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Films were shown about survivor Susan Pollack's return visit to Belsen camp, where she was held. She spoke of "mountains of corpses".

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During the ceremony eight of the survivors' grandchildren read names from a list of 3,000 people. who died in the Holocaust

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Prime Minister Tony Blair told the congregation "We must never dishonour their memory by allowing the ugly poison of racial prejudice and hatred to hold sway again."

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Some of the congregation carried photos of loved ones who had perished during the Holocaust.

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Thursday's event could well be the last major commemoration, as many Holocaust survivors are elderly.