Authorities in France's La Reunion have launched a probe to identify fraudsters who scammed a woman out of 830,000 euros by making her believe she had an online relationship with Brad Pitt.

The police are trying to locate the accounts that received the transfers from the French woman, who has lodged a complaint in the French Indian Ocean island of La Reunion, a police source said on Friday.

The woman, named only as Anne, told the TF1 channel that she had believed she was in a romantic relationship with the Hollywood heartthrob, leading her to divorce her husband and transfer 830,000 euros ($850,000).

The scammers used fake social media and WhatsApp accounts, as well as AI image-creating technology to send Anne what appeared to be selfies and messages from Pitt.

Anne, a 53-year-old interior decorator, spent a year and half believing she was communicating with Pitt and only realised she had been scammed when news emerged of Pitt's real-life relationship with girlfriend Ines de Ramon.

Since last autumn Anne has been in touch with Marwan Ouarab, the founder of the FindmyScammer.com website, in a bid to find the fraudsters.

According to French daily Le Parisien, which quoted Ouarab, the scammers — three men in their — are located in Nigeria.

"We would love for Interpol to take up the case," the newspaper quoted him as saying.

The woman has faced a wave of online harassment and mockery after the interview was broadcast, leading the programme to be withdrawn.

A representative for Pitt, 61, has warned fans to be wary of impersonation scams.

"It's awful that scammers take advantage of fans' strong connection with celebrities," a spokesperson for the Fight Club actor told US outlet Entertainment Weekly this week.