Police are not ruling out taking a closer look at people who left malicious comments on a Facebook page set up to help find a missing woman.
Acting Detective Inspector Mark Benefield says officers may follow up on malicious remarks.
Carmen Thomas, 32, from Remuera, Auckland, who worked as an escort, has not been seen since 1 July.
However, she was not reported missing until 13 July.
She has not contacted her son, aged five years, and her bank accounts are untouched.
Her car, a Nissan Pulsar, was found in Hamilton on 5 July.
Her family and friends have set up a Facebook group in a bid to find her but have now restricted access to it due to unkind comments.
Police revealed on Monday that they had joined the group and were monitoring it for clues.
Use of social media by police
Police are increasingly using social networking websites in their investigations.
In the latest example, they have joined a page on Facebook about Ms Thomas to try and get more information about her disappearance.
Police recently started an official national feed on Twitter and several districts have their own pages on Facebook.
Police in the Bay of Plenty were the first district to use Twitter. With people increasingly getting news from social networking sites, they say it is important for the police to be online too.
Another organisation using social media is the Automobile Association, which uses Twitter to keep motorists up to speed with traffic conditions. It says the updates are proving popular.
Orakei Basin being searched
Meanwhile, police are trawling through CCTV footage and continuing to speak to associates of Ms Thomas in Auckland and Hamilton.
Search and Rescue workers are scouring parts of Auckland's Orakei Basin as well as nearby parks.
Mr Benefield says they simply don't know what has happened to Ms Thomas and are exploring all possibilities.
He says her mother has made arrangements to come to New Zealand from South Africa later this week.
