New Zealand officially on high terror alert, in wake of Christchurch terror attacks

New Zealand's terror threat level has been lifted to high for the first time in its history, in the wake of what is now formally being described as a terrorist attack. 

Planes have been grounded following the attacks at two Christchurch mosques, which killed 49 people. 

Following high level security briefings with her top officials across police and intelligence agencies, Prime Minister Jacinda Ardern confirmed 10 people were killed at Linwood Avenue Mosque, three of whom were outside the mosque itself. 

A further 30 people have been killed at Deans Avenue Mosque. More than 20 seriously injured were also being treated in Christchurch A&E. That was less than two hours before Police Commissioner Mike Bush elevated the death count to 49.  

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Ardern said none of the four suspects, who police held in custody, were on the spy agencies' active watchlists. Questions would likely be asked later over how they managed to go unnoticed, given at least one of the suspects' appeared to have an active social media presence. 

That was a 28-year-old Australian who identified himself as Brenton Tarrant.

Ardern said the attack appeared to "have been well planned".

"Two explosive devices attached to suspects' vehicles have been found and they have been disarmed.

"There are currently four individuals who have been apprehended but three are connected to this attack and are currently in custody, one of which has publicly stated that they were Australian born," Ardern said. 

Intelligence agencies had briefed the Prime Minister that there was no reason to believe there were other suspects.

"But we are not assuming that at this stage. The joint intelligence group has been deployed and police are putting all of their resources into this situation.

"The defence force are currently transporting additional police staff to the region," Ardern said.

In lifting New Zealand's national security threat to high, she wanted to assure people "our agencies are responding in the most appropriate way. That includes at our borders".

Air New Zealand had cancelled all turbo prop flights out of Christchurch tonight, as they did not have security screening. Ardern also said there was a "heightened the level of response from our agencies at the border, at the airport, in fact at every level we have a heightened response". 

She gave a moving statement, that appeared to be couched in intelligence of the attackers' motives. 

"We, New Zealand, we were not a target because we are a safe harbour for those who hate.

"We were not chosen for this act of violence because we condone racism, because we are an enclave for extremism," Ardern said. 

"We were chosen for the very fact that we are none of those things."

And as she implored people not to share the hate-filled social media postings of the attackers, she also had a message for New Zealand's muslim community. 

"We are a proud nation of more than 200 ethnicities, 160 languages. And amongst that diversity we share common values. And the one that we place the currency on right now is our compassion and support for the community of those directly affected by this tragedy.

"And secondly, the strongest possible condemnation of the ideology of the people who did this," Ardern said. 

"You may have chosen us – we utterly reject and condemn you."

Earlier, she described the mosque attacks in Christchurch as one of New Zealand's "darkest days".

"Many of those who would have been directly affected by the shooting may be migrants to New Zealand. They may even be refugees here. They have chosen to make New Zealand their home, and it is their home. They are us. The person who has perpetuated this violence against us is not. They have no place in New Zealand."

"For now my thoughts and I'm sure the thoughts of all New Zealanders are with those who have been affected and all their families."

Ardern asked those in Christchurch to continue to follow advice from police. 

Commissioner Mike Bush has urged people to stay away from mosques across the country, and was warning those in Christchurch to stay indoors.