Women in the Illawarra have been receiving repeated calls from "a weirdo" asking if they wear high heels and underwear, after they placed ads on the online sales site Gumtree.
One woman in the Dapto area received text messages from the man after putting a child's item up for sale on Gumtree.
"[He] literally just asked about the item but I thought I'd be suspicious and wouldn't give too much away, so I said 'yes, it's available'," she said.
"Then the next text I received was odd - it was 'are you married or single?', so I thought okay, I'm just going to block this number."
The woman then searched for his number online and found other women with similar complaints.
"I could see pages of people saying 'oh yeah, this is a weirdo, he latches on, he texts all the time'," she said.
One of the complaints said the man asked whether she wore low or high heels, while another said he wanted to know if she wore "heels and underwear and if I would cheat on my husband".
I thought this is a little bit more concerning - he's not randomly picking people from across Australia.
The Dapto woman did not receive these more explicit messages because she immediately blocked his number, but said he would initially try to call or text every day and then at least three times a week since the first call seven weeks ago.
After she had a second look at the online list of complaints she noticed a number of the women were from the Illawarra, with suburbs like Port Kembla and Albion Park Rail mentioned.
"I thought this is a little bit more concerning - he's not randomly picking people from across Australia," she said.
"He's picking women from the Illawarra and then texting and calling."
The woman has not spoken to police about the calls and, when contacted by the Mercury, a police spokeswoman said there had been no complaints linked to the phone number.
The spokeswoman encouraged people to report calls and texts like these to the police.
"It is an offence to make menacing, threatening or harassing phone calls, and police treat these matters seriously," she said.
"Charges can be laid with this type of crime."
A spokeswoman from Gumtree said it had received a complaint "a few months ago" in relation to calls from this phone number.
"Gumtree promptly took steps to both assist the user who made the complaint and blocked the user who made the inappropriate contact," the spokeswoman said.
She said sellers can hide their phone numbers from prospective buyers.
"It's important for users to be aware of what personal information they are stating in their listing description, including phone numbers, as this is made available to all users," she said.
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