Auckland's Muslim community found six mosques vandalised and walls tagged in graffiti with the message "Londoners RIP" following the terrorist bombings in London that killed more than 50 people.
In what appeared to be a co-ordinated series of attacks in central, south and west Auckland, vandals smashed glass windows and doors and left variations of the same message in black paint on walls facing the street.
Muslim leaders and government ministers condemned the attacks.
New Zealand Federation of Islamic Associations president Javed Khan said it was the first time an attack on this scale had occurred against the country's 40,000 Muslims, about 25,000 of whom live in Auckland.
Mosques in Ponsonby, Mt Roskill, Blockhouse Bay, Ranui and two in Otahuhu were attacked in the early hours of the morning.
The Masjid Al-Mustafa mosque in Otahuhu was attacked on Thursday night and again on Sunday morning. There are about 14 Islamic places of worship in Auckland.
Khan said Muslims were "shocked and saddened" by the incidents in London and appealed to the community to be calm and tolerant about the overnight attacks in Auckland.
"We do not tolerate terrorism. Islam does not tolerate terrorism. It condemns anyone taking the life of an innocent person," Khan told a gathering at Masjid Al-Mustafa mosque.
Foreign Affairs Minister Phil Goff, one of four Labour MPs to attend the gathering, said the MPs had come to "express solidarity with you in the face of this mindless and stupid vandalism".
The other MPs to attend the gathering included Ethnic Affairs Minister Chris Carter and Police Minister George Hawkins.
Hawkins said police would be increasing the number of patrols at mosques in Auckland and Carter urged New Zealanders to offer their support and concern to the Muslim community in the face of "hatred, ignorance and bigotry".
Prime Minister Helen Clark was also quick to condemn the attacks, saying it was wrong to target the Muslim community in New Zealand in retaliation for the terrorist attacks in London.
"New Zealand's Muslim community, like all New Zealand communities, is overwhelmingly a law-abiding and peaceful community," she said.
Khan said it appeared from the similarly-worded graffiti that the attacks were linked. He hoped it was an isolated incident by a small anti-Islam group.
"We know the New Zealand wider community is a very tolerant community and they understand the Muslim community here is a very law-abiding and tolerant community and has always condemned terrorism wherever it has happened," Khan said.
Pakistan Association of New Zealand president Naveed Hamid said he condemned what happened in London and the vandalism in Auckland, saying Islam did not teach damage to any community.
"We oppose all terrorists, whatever their faith," Hamid said.
Five members of the Kelston Muslim community visiting the Ponsonby Mosque were asleep out the back when the attackers struck at 1.30am. Farhaz Rehmen said the men did not hear five glass windows being smashed.
Mosque secretary Firoz Patel said what happened in London had nothing to do with the Muslim community, which condemned the loss of innocent lives.
Auckland Central MP Judith Tizard visited the city's oldest mosque at Ponsonby, saying she hoped it was "stupidity not evil" behind the attack.
At the large Masjid mosque in Mt Roskill, where about 20 windows were broken and two graffiti messages painted, a senior member had only two words to describe the incident - "shocked" and "amazed".
New Zealand Jewish Council president Stephen Goodman deplored the "shameful" attacks and extended his sympathy to the Muslim community. Police are investigating the attacks.