The prolific author and human rights activist has died at the age of 87, according to Israeli media. Wiesel was best known for his book "Night," which described his experiences at the Auschwitz concentration camp.
Israeli newspaper Haaretz reported the Nobel Peace Prize winner's death on its website on Saturday. The Israeli center for Holocaust research, Yad Vashem, tweeted a message about the death of the writer and activist.
Germany promises 'never to forget'
Frank-Walter Steinmeier, Germany's foreign minister, called Wiesel "not only a great author, philanthropist and scholar … but above all, a tireless campaigner against hate, intolerance and violence."
In a statement posted on Facebook, Steinmeier remembered a "powerful" speech Wiesel delivered to the German parliament 16 years ago in which he called on Germany's younger generation "to create a better society than he, himself, had experienced in his childhood."
"It was a haunting message of hope and responsibility that we should take to heart, today," Steinmeier added.
German President Joachim Gauck also wrote to Wiesel's wife Marion, saying her husband's death was "a great loss" and that "we will never forget him."
"Your husband knew how to use vivid and empathic words to keep the memory of the darkest years of German history that he witnessed alive and to warn young people especially of the dangers of right-wing extremism and xenophobia," he said.
German Justice Minister Heiko Maas meanwhile tweeted that he felt "sadness over the death of Nobel Peace Prize Laureate Elie Wiesel. Witness of the Holocaust and chronicler of the indescribable."
"We must always take sides. Neutrality helps the oppressor, never the victim. Silence encourages the tormentor, never the tormented."
Reactions around the world
Israeli Prime Minister Benjamin Netanyahu hailed Wiesel as a "master of words" who gave expression to the victory of the human spirit over cruelty and evil with his unusual personality and captivating stories."
"Out of the darkness of the Holocaust, Elie became a powerful force for light, truth and dignity," he added.
In 2009, German Chancellor Angela Merkel and US President Barack Obama accompanied Wiesel on a tour of the Buchenwald camp. In his remarks on Wiesel's passing, Obama remembered the late author's comments during their visit:
"After we walked together among the barbed wire and guard towers of Buchenwald... Elie spoke words I've never forgotten: 'Memory has become a sacred duty of all people of goodwill,'" Obama said Saturday.
"Elie was not just the world's most prominent Holocaust survivor, he was a living memorial."
A tragic life
Eliezer "Elie" Wiesel was born in 1928 in Transylvania, Romania. He was deported to Auschwitz along with his family when he was 15 years old. His mother and younger sister died in the camp and Wiesel was moved to Buchenwald with his father, who died shortly before Allied forces liberated the prisoners in 1945.
According to a description of Wiesel's life on the Elie Wiesel Foundation for Humanity's website, the holocaust survivor lived in Paris after the end of World War II and studied to become a journalist.
In the years that followed, Wiesel was motivated to write his book "Night," which detailed his experiences in the Nazi concentration camps. It sold more than 10 million copies. "Night" was the first book of the Holocaust memorial trilogy, which included "Dawn" and "Day." He also authored over 60 books, mostly in French. These included "A Beggar in Jerusalem", "The Testament," "The Fifth Son" and his memoirs.
A strong supporter of Israel, Wiesel also took a keen interest in the cause of the Soviet Jews, Cambodia's refugees, the Kurds, and the apartheid in South Africa, among others. From time to time, Wiesel also attracted criticism for his uncompromising stances on certain issues.
Aside from his work as a writer, Wiesel also enjoyed a career as an academic, serving at the Boston, Columbia and Yale universities. Wiesel was honored with the Nobel Peace Prize in 1986 for his lifelong work on raising awareness about the holocaust, or the "Shoah," as it is known in Hebrew.
rs, mg, ss/bw (AFP, AP, dpa)