Survivors of Nazi death camps marked the 79th anniversary of the liberation of the Auschwitz-Birkenau camp during World War II with a solemn ceremony in southern Poland.

Some 20 survivors from various Nazis camps laid wreaths and flowers on Saturday at the Death Wall in Auschwitz.

Prayers were also held at the monument in Birkenau to mark International Holocaust Remembrance Day, memorializing about 1.1 million camp victims, most of whom were Jews.

The carefully preserved memorial site and museum are located near the city of Oswiecim.

International Holocaust Remembrance Day was observed in countries around the world. A memorial ceremony was held Friday in Ottawa, with Prime Minister Justin Trudeau and Conservative leader Pierre Poilievre both in attendance.

Almost 6 million European Jews were killed by Nazi Germany.

The Holocaust was the mass murder of Jews and other groups of people both before and during World War II.