New Zealand Prime Minister Jacinda Ardern has issued a "global call" to combat the "ideology" of racism after the terrorist attack by a white supremacist on two mosques last week that left 50 people dead and dozens more wounded. In one of her first interviews since the attack, Ardern rejected any argument that her country's policy of welcoming refugees and immigrants was to blame for the violence.

Asked if she was concerned about a rise of right-wing nationalism in her country, Ardnern told CBS News partner network BBC News that while it was an Australian citizen who committed the atrocity, "that is not to say that we do not have an ideology in New Zealand that would be an affront to the majority of New Zealanders."

But she said the problem of white nationalism is not unique to any one nation, and called on leaders around the world "to weed it out where it exists and make sure that we never create an environment where it can flourish."

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"What New Zealand experienced here was violence brought against us by someone who grew up and learned their ideology somewhere else. If we want to make sure globally that we are a safe and tolerant and inclusive world we cannot think about this in terms of boundaries," Ardern said.

She renewed her government's commitment to accept refugees, saying: "We are a welcoming country. I utterly reject the idea that in any way in trying to ensure that we have a system that looks after those who choose to call New Zealand home that we have perpetuated an environment where this kind of ideology can exist."

Ardern said on Tuesday in New Zealand's parliament that she would never refer to the perpetrator of the attacks by name. "He sought many things from his act of terror, but one was notoriety -- that is why you will never hear me mention his name."

Ardern on social media's role

Ardern has said social media platforms need to take more responsibility after the brutal attack on the first moque was livestreamed on Facebook for over 17 minutes, while an online manifesto spewed a message of hate replete with references familiar to extremist chat rooms and internet trolls.

The video of the attack shows the gunman taking aim with assault-style rifles painted with symbols and quotes used widely by the white supremacist movement online. While fewer than 200 people watched the video live, it was copied and shared widely by the "alt-right" community online.

Facebook told CBSNews.com sister site CNET that it removed the video and was pulling down posts that expressed "praise or support" for the shootings. It said it was working with police on the investigation. In a tweet, YouTube, which is owned by Google, also said it was "working vigilantly to remove any violent footage."

"We cannot simply sit back and accept that these platforms just exist and that what is said on them is not the responsibility of the place where they are published," Ardern said this week in a speech to New Zealand's Parliament. "They are the publisher, not just the postman. It cannot be a case of all profit, no responsibility."

Ardern also stated that although social media was not the cause of the massacre, it played a role in enabling hate to spread. "There is no question that ideas and language of division and hate have existed for decades. But the form of distribution, the tools of organization, they are new," she said.

The 28-year-old Australian suspect has been charged with murder over the shootings, and could still face more charges. Police have said he acted alone, but have not ruled out the possibility that others supported him.

The first funerals for the victims of the attack, who were largely immigrants and refugees, took place Wednesday with hundreds of mourners attending a service near the Linwood Islamic Centre in Christchurch, one of the two mosques attacked.