International Holocaust Remembrance Day was commemorated at UN Headquarters in New York, honoring the memory of some six million Jews who perished in the Holocaust during World War Two.

They died along with many other victims of what the UN chief António Guterres called "unprecedented, calculated cruelty and horror" on Jan. 28, UN News reported.

"From a deadly assault on a synagogue in the United States to the desecration of Jewish cemeteries in Europe, this centuries-old hatred is not only still strong – it is getting worse," said Secretary-General Guterres.

In Germany, the day before, a government delegation laid a wreath at the former Auschwitz-Birkenau death camp, Deutsche Welle reported..

At the commemoration, Foreign Minister Heiko Maas has warned Germany's Holocaust memory is under "pressure from the extreme right."

The German delegation led by Armin Laschet, the premier of Germany's most populous state, North Rhine-Westphalia, marked International Holocaust Remembrance Day at the site of the Auschwitz-Birkenau death camp on Jan. 27.

Laschet laid a wreath at the camp's execution wall along with a group of young German Jews, Muslims and Christians.

"Auschwitz shows what can happen when people's worst qualities come to bear," Laschet said. "The inconceivable crimes of the past must be a warning and an obligation for every new generation," he added.

PROLIFERATION OF NEO-NAZI GROUPS

In New York, Guterres commemoration message on Jan. 28, pointed to "the proliferation of neo-Nazi groups, and attempts to rewrite history and distort the facts of the Holocaust."

As the horrors of the Nazi concentration camps recede in time, leaving fewer and fewer Holocaust survivors, the need to be vigilant grows stronger.

In this year's theme: "Holocaust Remembrance: Demand and Defend Your Human Rights", youth are encouraged to learn valuable lessons from the Holocaust, such as acting forcefully against discrimination and defending essential democratic values.

Neo-Nazism and hate groups on the rise, together with other forms of hatred around the world, so the theme also highlights the 70th anniversary of the Universal Declaration of Human Rights and the Convention on the Prevention and Punishment of the Crime of Genocide.

Guterres recalled the quote by former Chief Rabbi of the United Kingdom, Jonathan Sacks: "The hate that begins with Jews never ends with Jews."

The UN chief said, "We see bigotry moving at lightning speed across the Internet.",

He pointed to "intolerance entering mainstream politics – targeting minorities, Muslims, migrants and refugees, and exploiting the anger and anxiety of a changing world."

"Now more than ever, let us unite in the fight for universal values and build a world of equality for all," said the UN chief.

As part of a week of commemorative activities, a ceremony on Jan. 28 in the UN General Assembly Hall featured first-hand testimony from survivors, memorial prayers, musical elements.

It heard the of Sara J. Bloomfield, Director of the United States Holocaust Memorial Museum, who after 81 years, continues working to raise Holocaust awareness, deepen the understanding of its hard-learned lessons, confront denial and advance genocide prevention.