The destruction of a cellphone tower north of Kaitaia is thought to be related to an online hoax linking 5G phone networks with the Covid-19 coronavirus.
The 4G tower on private farmland at Waiharara was a few days away from being turned on when it was irreparably damaged in an arson attack late last month.
The incident comes just as Northlanders' reliance on telecommunications has increased due to the Covid-19 lockdown, with businesses and schools forced to move much of their activity online.
There is no link between 5G and Covid-19 and there are no 5G cellphone towers in Northland.
And it followers a transmission tower fire at Baxter's Knob in Porirua on Thursday, which took out Kordia TV transmission gear and impacted cellphone service for some 15,000 2degrees customers.
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After the Baxter's Knob blaze, Spark, Vodafone and 2degrees called on police to investigate what they say is a string of threats and attacks.
And while none of the telcos would go on the record blaming anti-5G protesters, Geoff Thorn, head of the Telecommunications Forum (TCF), which represents the major telcos, told the Herald, "We know that damage to mobile networks in other countries has been linked to groups opposed to 5G. "
Detective Senior Sergeant Mark Dalzell, of Far North police, said the Kaitaia incident was under investigation.
''This was a tower that was being built to provide cellphone services and broadband internet to isolated rural communities. To have something like this damaged is an absolute backward step for our community,'' he said.
''If towers are damaged, it will cause disruption to everybody who relies on phone networks. We urge the community to be vigilant and report any suspicious activity straight away.''
The tower was being built by the Rural Connectivity Group, an initiative to bring 4G mobile and wireless broadband to ''mobile black spots'' in rural New Zealand as well as highways and tourist spots. The equipment is shared by Vodafone, Spark and 2degrees.
The Advocate understands the concrete base had been laid and all equipment was on-site, with the erection of the tower the only remaining step.
The New Zealand Telecommunications Forum slammed the Waiharara attack, which is understood to be the most serious of several incidents around the country in recent weeks.
"We condemn all acts of vandalism but it's even more frustrating to deal with an attack on critical national infrastructure during a time of national emergency,'' chief executive Geoff Thorn said.
''If cell towers are damaged and can't function, then the people they serve will not only lose internet access, there's the real chance that 111 calls will be unable to get through.
"The people responsible for these criminal acts are putting New Zealand lives in danger at a time when the country is making sacrifices to rid our communities of a deadly virus.''
The persistence of conspiracy theories around 5G even forced Prime Minister Jacinda Ardern to address the topic during last Wednesday's Covid-19 press conference.
RCG engagement manager Caitlin Metz said the group was ''deeply disappointed'' by the vandalism of its 4G site at Waiharara.
''The site was just days away from being operational. However, extensive damage to the tower, antenna and equipment needed to operate the site will cause significant delays to the facility being finished, as we try to source replacement equipment needed to rebuild the site.''
Metz said the RCG, which had essential service status, remained committed to improving the country's telecommunications infrastructure and getting sites ''on air'' as quickly as possible.
Spark spokeswoman Althea Lovell said the company was working with police after some of its cell towers around the country had also been vandalised, including by arson attempts, since the end of March.
''While the damage was fairly negligible, one event caused an outage of mobile and wireless broadband services in the surrounding area. We share the broader industry's outrage over acts of vandalism against critical infrastructure during a pandemic, when connectivity is more important than ever,'' Lovell said.
Various hoaxes and conspiracy theories claim links between Covid-19 and 5G, many of them propagated on social media platforms by celebrities and so-called ''influencers''.
■ Call police on 105 or Crimestoppers on 0800 555 111 if you have any information about the Waiharara attack.