Many Canadians were mourning the death of Nobel Peace Prize winner, Holocaust survivor, and author Elie Wiesel.

On social media, prominent Canadian politicians paid tribute to Wiesel, who was an advocate for victims of violence and oppression.

Prime Minister Justin Trudeau tweeted, "Elie Wiesel spent his life in service to humanity, keeping the memory of the Holocaust's horror alive. It is for us all to carry this torch."

Former prime minister Stephen Harper said he was "profoundly saddened" to hear that Wiesel died at the age of 87.

Harper said the world has lost a brilliant voice for "human dignity."

Former Ontario premier Bob Rae tweeted that he first heard Wiesel speak in 1969 and it made a lasting impression.

"Ever since then he has been for me a beacon of courage + hope," Rae wrote in a Twitter post.

The Romanian-born Wiesel is best known for his first book "Night," which told the story of his experiences in a Nazi concentration camp Auschwitz.

As a scholar and political activist, Wiesel was no stranger to Canada.

In 2012, Wiesel joined a number of Jewish faith leaders in condemning Canada's cuts to health care for some refugee claimants.

A letter written by Wiesel to the then Conservative government that was obtained by The Globe and Mail stated, "Today, as yesterday, a nation is judged by its attitude towards refugees."

His words did not sway the Tories who also introduced policies barring refugees who were not brought to Canada directly by the government from getting supplemental health benefits such as prescription drugs, vision care and dental care.

Wiesel had made a number of appearances in Canada including speaking to Toronto youth at a We Day event in 2009.

A YouTube video from the event shows Wiesel addressing thousands of children and teens with a message of peace.

"Your freedom should never be at the expense of someone who has no freedom... Do not let your hope be at the expense of another person's despair," he said.

Wiesel's death was announced Saturday but no further details were immediately available.

With files from The Associated Press