It follows similar incidents in the Far North and Porirua.
After the fire in Porirua on Thursday, which cut off mobile service to 15,000 2Degrees customers, telecommunications companies called on police to investigate what they said was a string of threats and attacks.
It comes at a time when dependence on telecommunications networks has grown because of the Covid-19 lockdown.
None of the telcos directly blame anti-5G protesters for the incidents, but Geoff Thorn, head of the Telecommunications Forum (TCF), told the Herald: "We know that damage to mobile networks in other countries has been linked to groups opposed to 5G."
Dozens of 5G cell towers have been burned down or vandalised in the United Kingdom, and authorities have blamed a baseless online theory that the technology is linked to the Covid-19 virus.
In the Manurewa video, a man filming the incident yells "F*** 5G" and "F*** the New World Order" - a reference to one variation of the conspiracy theory.
After the Kaitaia incident, which irreparably damaged a 4G cell tower, Detective Senior Sergeant Mark Dalzell of Far North police spoke of the harm to isolated communities.
''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.
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.
She said there was no link between 5G and the virus and urged anyone who was concerned to refer to the Ministry of Health and Chief Science Advisor websites.
Police said if anyone had information about the Manurewa incident they should call 105 or Crimestoppers anonymously on 0800 555 111.
