Olivia Marks-Woldman, chief executive of the Holocaust Memorial Day Trust, said:
We are deeply concerned by the lack of understanding among the population as a whole, and in particular the younger generations.
This research shows our work is more important than ever.
Genocide is not something that takes place by itself - it happens when a set of circumstances occur or are created, when racism and discrimination go unchecked and are allowed to divide communities.
A lot has been achieved, but there's plenty still to do to ensure that history does not repeat itself.
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