Dozens of Auschwitz survivors have laid flowers at the infamous execution wall in the former Nazi death camp, paying tribute to the victims of Adolf Hitler's regime exactly 72 years after the camp's liberation.
Elderly survivors also paid homage to those killed by wearing striped scarves reminiscent of the garb prisoners once wore there.
They walked slowly beneath the notorious gate bearing the words "Arbeit Macht Frei" (Work Will Set You Free) and made their way as a group to the execution wall, where they lit candles and prayed.
Janina Malec, a Polish survivor whose parents were killed at the execution wall, told reporters that "as long as I live I will come here", describing her yearly visit as a pilgrimage.
In Germany, foreign minister Frank-Walter Steinmeier said his nation remains committed to commemorating the genocide, honouring the memory of the victims and taking responsibility for the crimes.
January 27, the anniversary of the day that the Soviet army liberated the camp in German-occupied Poland in 1945, is recognized as International Holocaust Remembrance Day. Commemorative events are being held across Europe and Israel.
Mr Steinmeier said Auschwitz stands for all the death camps and the entire Nazi "persecution and murder machinery" which remains part of Germany's history.
He said that while Germany cannot change or undo what happened, the country has a continued obligation to commemorate the genocide, honour the memory of the victims and take responsibility for the crimes.
Noting the political instability in the world today, Mr Steinmeier said that "history should be a lesson, warning and incentive all at the same time".
He added: "There can and should be no end to remembrance."
Mr Steinmeier's statement came hours before he was due to hand over the post of foreign minister to the current economy minister, Sigmar Gabriel.
The Nazis murdered about 1.1 million people in Auschwitz during the Second World War - mostly Jews from across Europe, but also Poles, Roma, Soviet prisoners of war and others.
Poland's prime minister Beata Szydlo, who is from the Polish town where the Auschwitz memorial and museum is located, recalled the "destruction of humanity" and the "ocean of lost lives and hopes" in Oswiecim.
"It's an open wound that may close sometimes but it shall never be fully healed and it must not be forgotten," she said.
UN Secretary-General Antonio Guterres used the day of remembrance to warn against a rise in extremist ideology in the modern world: "Tragically, and contrary to our resolve, anti-Semitism continues to thrive.
"We are also seeing a deeply troubling rise in extremism, xenophobia, racism and anti-Muslim hatred. Irrationality and intolerance are back."
Mr Guterres vowed to "be in the front line of the battle against anti-Semitism and all other forms of hatred".
In Croatia, the Jewish community boycotted official commemorations, saying the country's conservative government is not doing enough to curb pro-Nazi sentiments there.
Community leader Ognjen Kraus, the coordinator of the Jewish communities in Croatia, said the decision was made after authorities failed to remove a plaque bearing a Second World War Croatian pro-Nazi salute from the town of Jasenovac - the site of a wartime death camp where tens of thousands of Jews, Serbs and Roma perished.