Tributes have poured in for Sir Nicholas Winton, who was called "Britain's Schindler" for saving the lives of Jewish children during the Holocaust, after he died aged 106.
Winton organised eight trains to carry 669 children from Nazi-occupied Czechoslovakia to London in 1939, fearing they would otherwise be sent to concentration camps.
He also helped to find foster families for the children once they arrived in England, but did not reveal his astonishing bravery for half a century, even to wife.
Home Secretary Theresa May, MP for Maidenhead where Sir Nicholas was a resident, said he was a "hero of the 20th century".
She said: "Against the odds, he almost single-handedly rescued hundreds of children, mostly Jewish, from the Nazis – an enduring example of the difference that good people can make even in the darkest of times.
"Because of his modesty, this astonishing contribution only came to light many years later. So many people owe their lives to Nicholas and it was fitting that, in his later years, he finally received the recognition he deserved.
"Maidenhead is rightly proud of all that he did, and we must ensure that his legacy lives on by continuing to tackle anti-Semitism and discrimination wherever it arises."
Prime Minister David Cameron, also paid tribute, saying: "The world has lost a great man. We must never forget Sir Nicholas Winton's humanity in saving so many children from the Holocaust."
Sir Nicholas, from a German-Jewish family, received a knighthood in 2003 and a Hero of the Holocaust medal at Downing Street in 2010 from Gordon Brown, who said he was "a real hero of our times".
Mr Brown added: "Anyone who had the privilege of meeting him immediately felt admiration, respect and were in awe of his courage.
"That courage led him to risk his life to save the lives of some of the most vulnerable people. His inspiration will live on."
On his 105th birthday the founder of the Czech Kindertransport operation was given a cake and card at his home in Maidenhead by newsreader Natasha Kaplinsky, who is a member of the Prime Minister's Holocaust Commission, and visited by Vera Schaufeld, one of the children he saved.
Ms Kaplinksy said: "Our country should be so proud of Sir Nicholas Winton. In the darkest moments of our history he showed how the best of humanity can still shine through.
"When I met him on his birthday last year I was struck by his incredible modesty. For years he didn't even talk about the extraordinary things he had done. It is humbling to think about the courage he showed in saving so many lives."
Last year, Sir Nicholas was awarded the Order of The White Lion by Czech president Milos Zeman.
Michael Zantovsky, Ambassador of the Czech Republic to the United Kingdom, became close friends with Sir Nicholas after meeting him over 20 years ago and described him as "a positive man who radiated good".
He added, "It was incredibly moving to be present at some of the gatherings of him with his so-called children and the children of his children. They all owe their existence to him."
Rabbi Lord Jonathan Sacks, who was Chief Rabbi of the United Hebrew Congregations of the Commonwealth from 1991 to 2013, called Sir Nicholas a "giant of moral courage" and "one of the heroes of our time".
He said: "Our sages said that saving a life is like saving a universe. Sir Nicholas saved hundreds of universes. He was a giant of moral courage and determination, and he will be mourned by Jewish people around the world."
World Jewish Relief, a UK-based international Jewish charity, paid its own tribute, saying: "Wishing long life to the family of Sir Nicholas Winton who has passed away at 106. His legacy, saving 669 children from the Nazis, lives on."
Current Chief Rabbi Ephraim Mirvis added that Sir Nicholas had showed "absolute commitment to fellow humans".
He said there were "thousands of descendants who owe their lives to him", adding many had been "inspired by his actions" to engage in charity work.
He said: "He was animated by a natural humane generosity of spirit and respect. He genuinely regarded what he had done as nothing more than any decent human being would have undertaken in the circumstances."