A British survivor of the 9/11 terror attacks said the "hope that tomorrow will be a better day" is what has kept her going through the past 20 years of grief and trauma.
Janice Brooks, then aged 41, was working on the 84th floor of the South Tower on the morning of September 11, 2001.
Today, speaking at a 20th anniversary memorial service in Olympic Park, east London, Ms Brooks described herself as "incredibly fortunate" to have made it out that day.
Her voice broke as she paid tribute to 61 of her colleagues who were tragically killed, while speaking in front of a four tonne twisted piece of steel from the South Tower which now stands as a memorial.
Ms Brooks, now 61, told the service: “That's why I'm here today, to not only mark the occasion, but to remind everyone of my friends."
Survivor Janice Brooks asked others to think about her friends who died on September 11 - but also all the survivors "because we are really struggling"
"Something that actually kept me going, not only on September 11, and in the days and the months afterwards, but still today - and that's hope," she continued. "The hope that tomorrow will be a better day. And you know what, it mostly is.
"But I think what I hope most of all, is that in the next hour or two that you can take some time to not only think about my friends but also everyone who died on September 11.
“And if I can be really indulgent, can I please ask that you spare a thought for all the survivors because we are still struggling.”
Now aged 61 and living in Norfolk, Ms Brooks had been in New York just three weeks when she was caught up in the tragedy that unfolded that morning.
Ms Brooks, who was an executive assistant to the chief executive of Euro Brokers, arrived at work at 7.30am and was typing up emails when she heard a "dull thud".
She and colleagues were unaware that American Airlines Flight 11 had hit the North Tower.
Someone on her floor suddenly screamed for people to evacuate and a “casual” Ms Brooks decided to call her boss in London before leaving the office - who shouted at her to "get out of there, a plane has gone into the building".
"Here was a guy who was 3,000 miles away from me, he was watching it on television, and yet I knew nothing and it was happening 200 yards behind me," she told the service this morning.
"Don't look up, don't look back, run": Ms Brooks recounts the moment she escaped from the 84th floor of the South Tower
The lives of 2,977 people from over 90 nations, including 67 from Britain, were claimed after Islamic extremists hijacked aeroplanes and flew them into the two buildings.
Jon Egan recounted the stories of his father and aunt Christine, originally from Hull, who died in the Twin Towers.
He told how he has named his newborn son Dean Michael after his father Dean managed to make a final call to his family as the towers crumbled.
Mr Egan, who was raised in the US but said he considers himself “a proud Brit”, told those gathered: “New York City was attacked. Washington City was attacked.
"But it was an attack on the world and it was an attack on our way of life.
“It was an attack on the free world.”
He urged people to remember how the world “came together” in the face of extremists following the attack - something he said was still important at “a time when so much is dividing us”.
In a video recording, Prime Minister Boris Johnson said that despite the lives taken, the terrorists had failed in their mission to instill “permanent fear” across the world.
He said: “They failed to shake our belief in freedom and democracy. They failed to drive our nations apart.”
The memorial was organised by Since 9/11, a UK education charity set up with the aim of ensuring the legacy of that day is one that builds hope from tragedy.
In respectful silence, the mourners in London heard speakers talk of the perished happiness of those who were killed and their loved ones, the survivors, and those who remember the shocking act of mass murder.
They heard of how the brutal intolerance which led to that day of terror still has to be fought against, not just potentially in Afghanistan - which once again has fallen to the Taliban - but also in British classrooms.
Caryn McClelland, deputy chief of mission at the US Embassy in London, said the memories of those who were killed will “never fade” as they are being recalled in “strength, love, bravery and hope”.
In thanking Britain for its ongoing support, including the poignant symbol of playing the US national anthem outside Windsor Castle on the orders of the Queen on Saturday, Ms McClelland said: “I am humbled to speak on behalf of the United States today to honour the true and enduring friendship you have always show us, not only in the best of times but in the very worst as well.”