New Zealand's prime minister declared Tuesday she would do everything in her power to deny the accused mosque gunman a platform for elevating his white supremacist views, after the man dismissed his lawyer and opted to represent himself at his trial in the killings of 50 people.

"I agree that it is absolutely something that we need to acknowledge, and do what we can to prevent the notoriety that this individual seeks," Prime Minister Jacinda Ardern told reporters. "He obviously had a range of reasons for committing this atrocious terrorist attack. Lifting his profile was one of them. And that's something that we can absolutely deny him."

She demurred about whether she wanted the trial to occur behind closed doors, saying that was not her decision to make.

"One thing I can assure you — you won't hear me speak his name," she said.

Later, in a passionate speech to Parliament, she urged the public to follow her lead and to avoid giving the gunman the fame he so obviously craves.

"I implore you: Speak the names of those who were lost, rather than the name of the man who took them," she said. "He may have sought notoriety, but we in New Zealand will give him nothing, not even his name."

The shooter's desire for attention was made clear in a manifesto sent to Ardern's office and others before Friday's massacre and by his livestreamed footage of his attack on the Al Noor mosque.

The video prompted widespread revulsion and condemnation. Facebook said it removed 1.5 million versions of the video during the first 24 hours, but Ardern expressed frustration that the footage remained online, four days later.

"We have been in contact with Facebook; they have given us updates on their efforts to have it removed, but as I say, it's our view that it cannot — should not — be distributed, available, able to be viewed," she said. "It is horrendous and while they've given us those assurances, ultimately the responsibility does sit with them."

New Zealand Prime Minister Jacinda Ardern is urging people to focus on the victims of Friday's mosque shootings. (Mark Tantrum/Getty Images)

Ardern said she had received "some communication" from Facebook's Chief Operating Officer Sheryl Sandberg on the issue. The prime minister has also spoken with British Prime Minister Theresa May about the importance of a global effort to clamp down on the distribution of such material.

Australian Prime Minister Scott Morrison also urged world leaders to crack down on social media companies that broadcast terrorist attacks. Morrison said he had written to G-20 chairman Japanese Prime Minister Shinzo Abe calling for agreement on "clear consequences" for companies whose platforms are used to facilitate and normalize horrific acts.

Lawyer Richard Peters, who was assigned to represent Brenton Harrison Tarrant at his initial court appearance on Saturday, told the New Zealand Herald that Tarrant dismissed him that day.

A judge ordered Tarrant to return to New Zealand's High Court on April 5 for his next hearing on one count of murder, though he is expected to face additional charges. The 28-year-old Australian is being held in isolation in a Christchurch jail.

"He seemed quite clear and lucid, whereas this may seem like very irrational behavior," Peters told the newspaper. "He didn't appear to me to be facing any challenges or mental impairment, other than holding fairly extreme views."

Peters did not return a call from The Associated Press on Tuesday.

Peters told the paper that Tarrant didn't tell him why he wanted to represent himself. He said a judge could order a lawyer to assist Tarrant at a trial, but that Tarrant would likely be unsuccessful in trying to use it as a platform to put forward any extremist views.

Under New Zealand law, a trial is "to determine innocence or guilt," Peters said. "The court is not going to be very sympathetic to him if he wants to use the trial to express his own views."

'Many questions' remain

Ardern previously has said her cabinet had agreed in principle on tightening gun restrictions in New Zealand and those reforms would be announced next week. She also had announced an inquiry into the intelligence and security services' failures to detect the risk from the attacker or his plans. There have been concerns intelligence agencies were overly focused on the Muslim community in detecting and preventing security risks.

New Zealand's international spy agency, the Government Communications Security Bureau, confirmed it had not received any relevant information or intelligence ahead of the shootings.

In parliament on Tuesday, Ardern said there are justified questions and anger about how the attack could have happened in a place that prides itself on being open, peaceful and diverse.

A St. John Ambulance member speaks to a mourner outside the Al-Noor mosque in Christchurch. (William West/AFP/Getty Images)

"There are many questions that need to be answered and the assurance that I give you is that they will be," she said. "We will examine what we did know, could have known or should have known. We cannot allow this to happen again."

Meanwhile, Christchurch was beginning to return to a semblance of normalcy Tuesday. Streets near the hospital that had been closed for four days reopened to traffic as relatives and friends of the victims continued to stream in from around the world.

Thirty people were still being treated at the Christchurch hospital, nine of them in critical condition, said David Meates, CEO of the Canterbury District Health Board. A 4-year-old girl was transferred to a hospital in Auckland and is in critical condition. Her father is at the same hospital in stable condition.

Relatives of the dead are still anxiously awaiting word on when they can bury their loved ones. Islamic tradition calls for bodies to be cleansed and buried as soon as possible. Ardern has said authorities hope to release all the bodies by Wednesday and police said authorities are working with pathologists and coroners to complete the task as soon as they can.

WATCH | CBC's Adrienne Arsenault and Briar Stewart report from New Zealand.