A 27-year-old man charged with threatening to kill worshippers at the Linwood and Al Noor mosques, has made his first appearance in the Christchurch District Court.
Police say he made the threats on the 4chan website which is favoured by white supremacists.
A cached version of the threat, which has now been taken down from the site, talks about the use of car bombs to attack the mosques on the two year anniversary of the 15 March terror attacks.
The man was arrested last night after a raid on his home by members of the Armed Offenders Squad.
He was granted interim name suppression and was remanded in custody until his next appearance on 19 March.
Meanwhile, the neighbours of the man charged over the threats say they are shocked at the allegations.
Both mosques were searched on Tuesday after a member of the public warned the police about a post on the website 4chan.
Police initially arrested two people after raids in Linwood and St Albans yesterday afternoon.
Neighbours living in the unit behind the St Albans house, who asked not to be identified, said they had hardly slept after returning late from work and reading the news.
They did not see their neighbour often and were not sure how long he had lived there.
Canterbury district commander superintendent John Price told a media briefing last night that any threat made on people and the community was not tolerated.
"We take all threats of this nature seriously and we are working closely with our Muslim community.
"Any messages of hate or people wanting to cause harm in our community will not be tolerated - it's not the Kiwi way."
The Muslim community was spoken to "pretty soon" after police were made aware of the threat, he said.
Abdigani Ali, the spokeperson for the Muslim Association of Canterbury, said they were quickly notified of the threat by the police.
"The community has mixed emotions at the moment. Some people are in shock and some people are coping with it the best way they can. This was not only a threat to the Muslim community but a threat to the New Zealand community as well, so there are a lot of non-Muslims as well that are concerned about this issue.
"But the New Zealand Police have done a great job at identifying this risk and arresting those involved."
Imam Ibrahim Abdul Halim was the Imam of the Linwood mosque on the day of the attack in 2019.
He is now Canterbury University's first Muslim chaplain, and says it is hard to grasp that some people still misunderstand the Muslim faith.
"We are not against any one. We love everyone. We need to link our hands with everyone. Why do people use us like that. I'm really very sad. Very sad."
Halim said he was now in two minds about whether it would be safe to attend the upcoming memorial event planned to mark two years since the mosque attacks.
A spokesperson for the Islamic Women's Council, Anjum Rahman said the threats were very unsettling for the Muslim community, but she was glad that they were reported to the police quickly.
"I understand there is a group of people, volunteers, who have accounts in some of these places and are watching what is going on and they referred this to the police."
GCSB and SIS Minister Andrew Little defended the intelligence teams monitoring threats against New Zealand Muslim communities.
Little said the security monitoring team looked at millions of posts daily on multiple websites.
"A lead was provided to the police, I can say that the police and the intelligence agencies worked together to ensure that the police were able to apprehend somebody, that person is now before the courts. That is the system working."