The entrance to the Al-Noor mosque in Christchurch. (file photo)

Members of Christchurch's Al Noor mosque have increased their security measures following an apparent terror threat, two weeks before the first anniversary of the March 15 attack in which 51 worshippers were gunned down.

The threat was issued on Sunday night on an encrypted messaging app, accompanied by a photo of a masked man sitting in a car outside the mosque.

A police spokeswoman has confirmed an investigation into the threat is under way.

Prime Minister Jacinda Ardern said it was "hard for me to believe" that anyone would threaten the Muslim community in such a way.

READ MORE:

* Spy chiefs reveal Kiwis inspired by March 15 terror attack among those monitored

* What's public in the case of the soldier arrested for breaching national security

* Counter-terrorism detectives question far-right soldier's family and friends

* Far-right extremists were on the Government's radar before mosque attack

Christchurch's Al Noor was one of two mosques targeted in a racially motivated mass shooting on March 15, 2019. The alleged terrorist, an Australian national, awaits a trial due to begin in June.

GEORGE HEARD/STUFF Police and St John staff outside the Al-Noor mosque after the March 15, 2019 terror attack. (file photo)

Asked if she had been briefed on the threat, Ardern said she had only seen public reporting.

"I will be amongst many New Zealanders who will be devastated to see that, as we head towards the one year anniversary of a most horrific terror attack on the Muslim community, that they should then be the target of this kind of activity."

The threat and accompanying photo was posted anonymously to more than 2000 followers on a messaging channel on the encrypted communication app Telegram.

Do you know more? Email thomas.manch@stuff.co.nz

The image shows a man wearing dark sunglasses and a balaclava printed with an image of a human skull. Through a car window the front of the Al Noor mosque can be seen.

In the background, four people are visible at the entrance of the mosque.

The message attached, written in both English and Ukrainian, implies the people at the "same mosque" would be greeting each other for the "last time". A gun emoji, or symbol, is also used in the message.

The image was posted on a messaging channel dedicated to celebrating the March 15 terror attack.

ROSS GIBLIN/STUFF Prime Minister Jacinda Ardern says its "hard for me to believe" that such a threat would be made outside the Al Noor mosque.

Canterbury Muslim Association spokesman Tony Green said the community has increased security measures at the Al Noor mosque.

"We've looked closely at the building itself and we're going to increase our collective level of vigilance," he said

"We don't want to give [the threat] more credence but we also don't want to be flippant about it."

Canterbury District Commander Superintendent John Price said while there would be a "heightened response" from police, no general arming order had been issued.

"We have increased patrols at the mosque and we've been working with the community and we also have the Eagle [helicopter] capability that will be providing reassurance and visibility around both mosques."

He said the threat was being treated very seriously and would not be tolerated.

"This is just not the New Zealand way, it's not the way that we behave as a community and people will be held to account for any behaviour that's not in line with the law."

Price said officers from outside the Canterbury region were expected to be brought in to Christchurch in the coming weeks to bolster police capabilities.

Islamic Women's Council national co-ordinator Anjum Rahman said police were already investigating when she notified them of the threat early on Monday morning.

It would be helpful to have a visible police presence at the mosques as the anniversary of the attack approached, she said.

"There have been threats, more oblique threats, to other mosques in the last six to eight months or so. We know there is ongoing activity, I would just say the public should be vigilant and report anything that they see as suspicious."

CHRISTEL YARDLEY/STUFF Islamic Women's Council national co-ordinator Anjum Rahman said police were already conducting enquiries into the threat.

Security Intelligence Service director Rebecca Kitteridge last month warned some Kiwis have been inspired by the March 15 terror attack, and monitoring such people had been difficult.

An SIS spokesman declined to comment on the specific threat.

In February, Kitteridge said New Zealand's spy agencies were investigating some 30 to 50 people for a potential terror risk at any one time.

She said it was challenging to monitor such people as they "tend to live in encrypted chat rooms" – such as Telegram.

Kitteridge would not say if any specific terror plans had been intercepted.

Messages on the Telegram app first alerted the public to the arrest of a 27-year-old soldier connected to far-Right groups, in November 2019.

The soldier is awaiting a military trial, facing charges of accessing a computer system for a dishonest purpose and for disclosing information that prejudiced the security or defence of New Zealand.

'BRACE YOURSELF'

Massey University sociologist Paul Spoonley, who has previously written about the far right in New Zealand, said he was "really worried" a threat had been made so close to March 15.

He said the community should be braced for some extreme comments to surface online that are supportive of the March 15 attacks.

"I'm not surprised, but I'm really disappointed. Even before the shootings there was a lot of Islamaphobic content, and I really don't think most people appreciate how much there was," he said.



The number of white supremacists in New Zealand tended to be "fluid". Spoonley said there was currently a core of about 250 key members.

Authorities across western nations continue to grapple with the terror threat posed by adherents to far-Right and white supremacist ideologies.

The director of the Australian Security Intelligence Organisation, Mike Burgess, last week told reporters that small cells of such extremists posed a growing and enduring threat.

Days earlier, in the United States, the New Jersey Office of Homeland Security increased the terror threat level regarding homegrown white supremacists to "high".

* Correction: A threat to Al Noor Mosque on an encrypted messaging app was in English and Ukrainian, not Russian as reported yesterday.