Online retailer Amazon is known for offering deals on thousands of book titles, but the company has recently been in the news for selling books that deny the Holocaust, and glorify rape and incest.

A number of groups, including the World Jewish Congress, are calling on Amazon to stop selling books that deny the Holocaust, as well as Nazi paraphernalia from its website. They say if the retailer refuses, the next step will be a boycott.

"No one should profit from the sale of such vile and offensive hate literature," WJC Executive Vice President Robert Singer wrote in a letter to Amazon CEO Jeff Bezos last week.

The online retailer made headlines earlier in October when a media report revealed that Amazon carries a number of books with the titles like "Did six million really die? The truth at last," "The Synagogue of Satan" and "The myth of extermination of the Jews."

Books glorifying rape and incest were also reported to be have been available for purchase on the company's website.

An Amazon call centre agent told CTV News that the company doesn't have a policy that specifies the types of books it can offer for sale.

"We actually really do not have any specific policy on those kinds of books," the agent said.

But many Jewish and women's groups say there should be limits.

"It runs contrary to Canadian values. It's against the law and I think that Amazon should rethink its policy," said Frank Dimant, CEO of B'nai Brith.

Civil liberties groups say banning books and defining what constitutes hate speech isn't that simple.

Mailing obscene, immoral or hate material is illegal -- but it’s up to interpretation and rarely enforced.

Cara Zwibel from the Canadian Civil Liberties Association said the group strongly believes in freedom of expression.

"We believe in very broad and robust protections for freedom of expression, even for expression that we and most Canadians would consider extremely offensive," she said.

In 2009, Amazon did stop selling some materials after its German subsidiary was sued for carrying more than 50 pro-Nazi books. However, most of those same books are still available for purchase on Amazon.com and Amazon.ca.

Holocaust survivor and author Peter Kubicek said Amazon is disseminating hate literature.

Kubicek's own memoir of the time he spent in six German concentration camps during the Second World War can be found on Amazon, alongside a number of books that deny the Holocaust.

The notion doesn't sit well with him.

"It's quite obviously objectionable. It's quite obviously the equivalent of hate speech," he said.

Amazon customers can also buy all types of Nazi regalia on the website, including flags, hats and knives.

"You can equip an entire neo-Nazi hate club just by going to your Amazon website," Dimant said.

Despite the claim of Amazon's customer service representative, the company does have a policy on content.

The policy states that "Amazon.com reserves the right to determine the appropriateness of items sold on our site. Also, be aware of cultural differences and sensitivities. Some items may be acceptable in one country, but unacceptable in another. Please keep in mind our global community of customers."

Amazon refused to comment to CTV News.

With a report from CTV News' Peter Akman