IT is essential that the Holocaust is never, ever forgotten, Jonathan Dimbleby told a crowd of 1,500 in Manchester on Wednesday night.
"The Holocaust must not be allowed to drift into the midst of time," the broadcaster and journalist said at the Manchester Jewish community's annual Yom Hashoah commemoration.
"The monster of antisemitism can only too easily rear its ugly ahead and demand to be heard as though it was an acceptable point of view."
Mr Dimbleby's late father Richard, the BBC's first war correspondent, broadcast the first report from Bergen-Belsen concentration camp in Germany.
An extract of it was played at the emotional and tear-jerking ceremony, held at EventCity, Trafford Park.
Mr Dimbleby explained: "Initially, the BBC did not want to broadcast it, but my father told them he would resign if they did not do so.
"He wanted to express disgust, horror and outrage over what he saw in Belsen.
"My father entered the world of a nightmare.
"He bore witness to an atrocity which people are now grievously familiar."
Mr Dimbleby said his father had told fellow reporter Wynford Vaughan-Thomas that he would "never be able to get the filth about what he saw out of his mind".
"He broke down in tears several times while recording his report from Belsen," Mr Dimbleby added.
"None of those millions who heard it would ever forget it.
"They heard the shock, consternation, the outrage and the incontestable evidence.
"His word are ones which continue to resonate down the years, except by those sorry specimens of our species who, even today, would avert their sorry gaze to the truth or do not care about it.
"My father never spoke to his children about Belsen, but it became part of his DNA.
"It formed his entire world for the rest of his life.
"I was at Belsen a couple of months ago as part of a documentary on the Second World War which I am filming for the BBC.
"The birds seemed not to sing - it was impossible not to be moved by the absence of life."
The ceremony marked the 70th anniversary of the liberation of the concentration camps, including Belsen.
Freedom came to Belsen 70 years ago on Wednesday.
Angela Seitler and Rob Kanter described some of the horrors which camp inmates suffered.
"They had endured six long years of brutality, savagery and mass murder," Mr Kanter said.
"We are here to honour the survivors and victims of the Shoah, then remember the liberation from the iron and murderous grip of Nazi Germany."
Mrs Seitler quoted political activist and Holocaust survivor Elie Wiesel, who said: "To forget the dead would be akin to killing them a second time".
She added: "The liberation of the camps happened haphazardly as the Allies moved across Europe in 1944.
"The first major camp to be liberated was Majdanek, in Poland, in July, 1944.
"The Nazis, surprised at the rapid Soviet advance, quickly tried to hide the evidence.
"Those inmates still alive were taken on death marches for hundreds of miles in freezing weather and without food, clothing or shoes."
Mr Kanter said: "Tens of thousands died or were shot simply because they could not keep up."
Survivor Chaim Ferster told his story. And his sister Manya Stern's story was told by Mr Ferster's daughter-in-law Shelley.
Raised in the Polish city of Sosnowiec, near the German border, Mr Ferster, now 92, said: "Our home town was quickly overrun by the Nazis.
"They persecuted Sosnowiec's 28,000 Jewish community.
"Life became more and more difficult and there were little Jewish children on the streets crying, asking where their mummies and daddies were."
Mrs Ferster explained how Mr Ferster and Mrs Stern, who were forced to live in the Sosnowiec ghetto, were rounded-up, with many other families, and told to go left or right.
Forcibly separated, they never saw their parents again.
Mrs Stern was sent to a labour camp, forced to do backbreaking work every day.
"People were rounded-up and indiscriminately killed," Mrs Ferster said.
"That one day she may be free seemed unbelievable to her.
"She and other prisoners were made to march for 21 days, despite being cold, starving and exhausted."
In November, 1944, Manya was sent to Belsen, where typhus raged through the camp and death hovered everywhere.
Mr Ferster was sent to various labour camps and concentration camps, including Buchenwald and Auschwitz, where he was tattooed with the number B10924.
Stricken with emotion, he said: "People were shot on the marches and left at the side of the road.
"At Buchenwald, several hundred prisoners were taken out daily and shot nearby.
"When the Americans liberated us, we kissed and we cried.
"We could not believe it."
Miraculously, Mr Ferster and Mrs Stern were later reunited, despite her being sure all her family had died.
They then travelled on to Sweden, which offered shelter to Holocaust survivors, before moving to England in 1946, thanks to their paternal uncle Bernard, who lived in Manchester.
Mr Ferster added: "The six million died only because they were Jewish men, women, children and babies.
"Thank God, we have had many blessings in the 70 years since the liberation."
Hazel Verbov spoke of her late father, Rev Leslie Hardman, who was the first Jewish British army chaplain to enter Bergen-Belsen.
"He thought he had seen everything until he arrived in Belsen," she said.
"The inmates saw the Star of David on his cap and tunic and thought he was the Messiah."
Attached to the 8th Corps of the British 2nd Army, Liverpool-raised Rev Hardman entered Belsen two days after it had been liberated.
He supervised the burial of around 13,000 victims "to restore in death the dignity they'd been denied in life," Mrs Verbov explained.
"My father recited El Maale Rachamim at the graveside. He also circumcised babies who had been born in the camp and conducted a marriage between a survivor and a British sergeant who liberated her.
"Knowing Yiddish, he could speak with a large proportion of them and did his utmost to boost morale and provide help."
She said her father suffered afterwards what today would be labelled as "post-traumatic stress syndrome".
Mrs Verbov recalled: "He could never forget the horrors and regularly suffered nightmares. Belsen left an indelible mark on him and he briefly questioned his own faith.
"My father later avowed that he did not lose his faith, but some of the words of his prayers said at Belsen were stuck in his throat.
"He recovered his equanimity, in no small measure thanks to my mother's devotion and support."
Rev Hardman later told a BBC reporter: "If all the trees in the world turned into pens, all the waters in the oceans turned into ink and the heavens turned into paper, it would still be insufficient material to describe the horrors these people suffered under the SS".
Warren Bomsztyk, the son of the late Polish-born Holocaust survivor Mayer Bomsztyk, said that second, third and fourth generations carried the survivors' memories with them.
He recalled: "My father was 16 when he was brought to the UK in August, 1945, after being liberated from Theresienstadt.
"He didn't speak English and he had no money, yet he began his life again. My father learned a trade, married and had three children and 10 grandchildren.
"He was so proud of the family he created."
Manchester Jewish Representative Council president Sharon Bannister said: "Yom Hashoah endures as a date critical in Manchester and around the world.
"Many survivors have contributed so much to our community.
"It is a privilege to honour those still with us and the six million who perished in the Holocaust."
Polish-born survivor Sam Laskier read the survivors' legacy, while daughter Shelley and granddaughter Lauren read the pledge of the second and third generation.
Avrom Aronson recited El Maale Rachamim and Rev Gabriel Brodie recited kaddish.