The Allianz Park stadium in Hendon is more accustomed to noisy crowds cheering on the Saracens rugby union team. But amid grey clouds and blustery winds on Sunday, it was transformed into a place of solemn tribute.

Around 5,000 people attended Britain's largest ever Holocaust memorial event, the national Yom Hashoah ceremony, which was relocated to north-west London from its normal Hyde Park venue to attract a bigger turnout.

This year's event, supported by more than 120 communal organisations, also marked the 70th anniversary of the end of the war and the liberation of Auschwitz, Bergen-Belsen and other camps.

Charity leaders, diplomats, families and Shoah survivors mingled on the East Stand terraces as a service on the theme of "I remember" covered the situation in Europe in the 1930s and '40s, Britain's role in the Kindertransport, current concerns and the future of Holocaust education. One of the first speakers on the stage, erected at the side of the rugby pitch, was Buchenwald survivor Ben Helfgott, who became a British Olympic weightlifter.

He recalled his escape from Nazi persecution, telling the crowd: "It is the truth and it must be remembered. We have never forgotten the lives that were destroyed. Remember being here today, standing together as a community and pledging to take responsibility.

"Our generation of survivors cannot last forever, but you will remember. We are passing the baton of trust to you."

Testimony from survivors was broadcast throughout the ceremony on a giant screen next to the stage. Among those featured in the clips was Eva Behar, who described her experience in Bergen-Belsen.

"You are lying there with fleas eating you up," she began, tears rolling down her cheeks. "I don't think you can comprehend it. I contracted typhus and was very sick but my luck was that the block sister liked me. She did not give me up to the hospital and I got over the typhus in the barrack.

"I was there to see the British troops come in. The feeling of liberation? There are no words. You are free and you can go and do whatever you like. There was unimaginable joy, but you don't have the strength to be joyful."

Her testimony was followed by the broadcast of a BBC recording made in Belsen by Richard Dimbleby following the camp's liberation. It included survivors singing an early version of what would become Israel's national anthem. The crowd listened in silence, later performing its own rendition of the modern Hatikvah with added gusto.

The emotion in Chief Rabbi Ephraim Mirvis's voice was palpable as he recalled his visit to Auschwitz last week as part of Britain's March of the Living delegation. "The fact that today we are here together to mourn, united as a community in our thousands, is a cause for hope for our future."

He urged the audience to work to ensure that antisemitism would be "neutralised" in modern Britain.

Attention then switched from the stage to the stands as six memorial candles were lit by communal leaders, survivors and the grandchildren of those who lived through the Shoah.

A minute's silence was broken only by a blast of the shofar from Rabbi Barry Marcus, who has accompanied thousands of British schoolchildren on visits to Auschwitz-Birkenau.

As a chazan performed the El Maleh Rachamim memorial prayer, calling out the names of concentration camps in haunting tones that echoed around the arena, a lone police van could be seen in the distance patrolling the grounds - a chilling reminder of the threat Jewish communities still face.

The need for neutrality in advance of the general election meant a restricted role for politicians, but a video message from London Mayor Boris Johnson included remarks celebrating the fact so many survivors had made the capital their home.

Praising the "ambition and imagination" of the event, Sir Peter Bazalgette, chairman of the new UK Holocaust Memorial Foundation, pledged to encourage society as a whole to take an active role in remembrance.

Israel's ambassador to Britain, Daniel Taub, introduced a choir made up of more than 160 pupils from Jewish primary schools. "You are not old enough to fully understand what this day is about, but one day you will be and it's important you can say 'I saw survivors who were there'," he told them. The pupils needed to be the bulwark against future Holocaust denial.

The children's performance of composer Stephen Melzack's Never Again left many spectators quietly wiping away tears as they filed out of the stadium.