Churches across the UK have held special services and said prayers to remember the millions of Jews killed in the Holocaust.
Holocaust Memorial Day is marked around the world each year on 27 January, the date that Auschwitz concentration camp was liberated 68 years ago.
More than a million people, mostly Jews, died in the camp at the hands of the Nazis.
The day was marked by churches around the theme of Communities Together: Build a Bridge.
Readings and prayers were selected with a view to inspiring closer relations within communities.
The Reverend David Gifford, chief executive of the Council of Christians and Jews, said that the horrors of the conflict in Syria and violence in northern Nigeria were a reminder that the world today still needs bridge builders.
"Holocaust Memorial Day this year points very directly to the fact that our common future with reconciliation and peace in our communities will be a pipe dream unless courageous men and women take the risky and costly path of reaching out to those who are different from themselves," he said.
Ceremonies of remembrance were also held at the National Memorial Arboretum in Staffordshire and at the Millennium Bridge in London.
David Cameron tweeted his support: "Memorial Day is a day to remember the innocent victims of the Holocaust, and re-commit to combat all forms of racism & prejudice."