She was transferred to a person claiming to be Sergeant Nathan Raymond Shaw, a fake name, who threatened the woman with arrest.
The victim was told she had 24 hours to organise childcare if she had children. She asked a number of questions and said that the answers were very convincing.
The scammers had personal information about the woman.
Pepere said the victim then contacted police who confirmed it was a scam.
"This is a variation on previous scams seen by police, where the scammer claims to be from a widely recognised organisation in order to appear legitimate," she said.
"These scams run constantly and, while most people will not respond or buy into them, some people are more vulnerable."
She asked people to remind vulnerable and elderly family members about the tactics used and that government agencies would never ask for passwords, credit cards or bank details.
"Do not engage with anyone on the phone if you think you are being scammed – hang up immediately and report the incident. If you are in doubt as to a caller's legitimacy, ask if you can call them back, or just hang up," Pepere said.
If you think you are a victim of a scam, report it to your bank and the local police immediately.
