Attorney-General, Simon Corbell, said the fraudulent sale of a home is one of the most serious types of scam and traditionally occurred while the owner was living or travelling overseas.

He said real estate professionals needed to exercise due diligence in all transactions, especially those from overseas.

“Independently confirm any change in contact details for the properties you manage dealing with the real owner. Signatures should be checked with originals on file. Have any doubtful documents verified by the issuing authority," he said.

“Homeowners, particularly absentee owners, are also warned to be vigilant. Have suitable protocols in place, for example, security questions, to prevent the possibility of your home being sold without your knowledge or permission.”

The warning follows the recent arrests of two Nigerian men and a South African woman in South Africa over the attempted fraudulent sale of a unit in Mandurah, south of Perth.

Asanda Zimkhitha Cwayi, 28, Magnus Ikechukwu Kamah, 38, and Nbubusi Sunday Okeke, 34, have all been charged with fraud, forgery and uttering over the alleged property scam.

It is alleged the Mandurah real estate agency managing the Greenfields property on behalf of its South African owner was contacted by someone claiming to be the real owner and requesting a change of email address.

Two weeks later, a request to sell the property was received and agreements were signed with forged signatures and exchanged electronically before the property was put on the market.

An offer was made and accepted by the person claiming to be the owner. The alleged scam was uncovered when documents were sent to the owner's address in South Africa.

WA Police Major Fraud Squad Detective Senior Sergeant Dom Blackshaw said offenders attempting such frauds could not hide behind international borders.

"We will be working effectively and cooperatively to make sure they are identified and caught," he said at the time.