Christchurch mosque shootings: Two-minute silence on Friday to honour the dead, PM Jacinda Ardern announces

A two-minute silence will be held on Friday to commemorate the one-week anniversary of last week's massacre.

Prime Minister Jacinda Ardern made the announcement during a visit to Christchurch today.

In a separate event, state broadcasters Radio NZ and TVNZ will also play the Islamic call to prayer.

Two minutes' silence was chosen over the usual one minute because of the magnitude of the tragedy; a two-minute silence also took place to commemorate the Pike River explosions in 2010.

The first burial of those who died took place today - two refugees from Syria - and Ardern said they should have been safe in New Zealand.

"I cannot tell you gutting it is to know a family came here for safety and refuge, and they should have been safe here," Ardern said.

She confirmed 30 of the 50 bodies of those who died had now been returned to their families.

Many families have expressed frustration at the length of time it has taken for bodies to be returned, and Ardern said she shared that frustration.

That had nothing to do with a lack of resources, she said, but the complex process of identification.

She added that she wanted to look at the international and domestic thresholds that needed to be met for formally identifying dead bodies.

She also responded to reports that Islamic State had called for reprisals to Friday's attack, saying that the New Zealand Muslim community had only expressed "a rejection of extremism, violence and hate".

Before today's press conference, Ardern met with police officers who were first on the scene at Masjid Al Noor and had to secure the mosque as well as give first aid to the critically injured.

She also met St John's first responders and thanked them for their service on New Zealand's "darkest day".

"I have no doubt you saved lives," she told them.

Prime Minister Jacinda Ardern hugs and consoles a student during a visit to Cashmere High School in Christchurch today. Photo / AP

In the morning Ardern visited Cashmere High School, where she was welcomed by a passionate haka.

Cashmere High lost Year 10 student Sayyad Milne and Year 12 student Hamza Mustafa on Friday.

Hamza's father Khaled was also killed. Hamza and Khaled were the first of the deceased from Friday's shooting to be put to rest today.

At the school assembly, Ardern shared an embrace with Bri, a 13-year-old Year 9 student, who opened the question and answer session by asking her: "How are you?"

"I am very sad," Ardern replied.

Asked about the gunman during the session, Ardern told students to focus on the victims.

"You know some of the young people who lost their lives on Friday. It's their names and stories that we need to keep telling. It's them we need to honour.

"If I can request one thing, don't say his name, don't dwell on who he is."

She said it was everyone's responsibility to fight racism.

Ardern praised a vigil that was held on Monday in Hagley Park and coordinated by Cashmere head boy Okirano Tilaia.

Ardern said social media could be used as a force for good and referred to the fact that thousands of students knew about the vigil through social media.

"Never underestimate the power of just sending a message, looking out for someone, performing a haka. There is power in that."

But she also cautioned the students about the perils of social media, and dozens of hands shot up when she asked the students if any of them had had negative experiences online.

"Racism breeds extremism ... I alone cannot do that by myself. I need help from every single one of us.

"Let New Zealand be a place where there is no tolerance of racism, ever."

She told the students that help was available, if needed.

"It's okay to grieve, it's okay to ask for help."