It also provides links to a US website selling SafeSound personal alarms, which it claims are ''saving millions of lives'', for about NZ$60.
The problem is, both the attack and the police officer's advice are fiction.
The Advocate's Kerikeri office has fielded calls from people who read about the attack and wondered why it hadn't been reported in the newspaper.
One woman, who did not want to be named, said she became suspicious because the location of the attack given in the story — Kerikeri, Whangārei or Auckland — changed depending on where she was when she used her laptop. Other details of the supposed attack remained the same.
One of her colleagues, however, was convinced that an elderly woman really had been assaulted in a Kerikeri supermarket carpark, and that she had escaped only thanks to a personal alarm.
A spokesman for the Commerce Commission said it had not investigated or received any complaints about the SafeSound advertisement so couldn't comment on it.
One of the Commission's roles was to enforce the Fair Trading Act which prohibited false, misleading or unsubstantiated claims by businesses.
It was complicated but the Commission could take action against overseas businesses.
The Commission had received more than 550 complaints about Swiss ticket re-seller Viagogo, for example, and was taking the company to court.
Police have also been contacted for comment.
The top of the fake news story carries the word 'Advertorial' while the bottom of the page has a disclaimer saying it is not an actual news article.
However, people who contacted the Advocate didn't see the disclaimer, which follows a series of reader comments which also appear to be fake.
In any case a disclaimer does not allow an advertiser to make false claims.
The company marketing the alarms gives an address in Idaho, USA. 'Buyer beware'
Northlanders need to be wary about what they buy — or believe — on social media, Consumer NZ says.
Consumer adviser Maggie Edwards said the SafeSound personal alarm advertisements appeared to be a breach of the Fair Trading Act because the company was making claims that could not be proven.
The Commerce Commission could order a company to back up its claims with evidence and impose fines if it failed to do so.
She urged people not to believe everything they read on social media.
''Facebook, or links you follow from Facebook, can be a bit of a Wild West. So we'd say buyer beware, and get your information about local events from a reputable local newspaper,'' Edwards said.
The company's website also used every hard-sell technique in the book, including limited-time discounts and claims the product was about to run out.
If anyone had tried to buy one of the devices but it hadn't turned up, they should contact their credit card company about getting their money returned through a charge-back.