Between Jan and May 2012 over 30 elderly residents of San Francisco were scammed by at least one trio of perps (all Cantonese-speaking woman) who managed to convince that the elderly is wearing some jewelry that were inhabited by evil spirits, and they'll perform exorcism for a small fee. The victim is encouraged to go to the bank safe deposit box to take out all of the jewelry to it can be "blessed" as well. Sometime after the jewelry was handed over and handed back, worthless trinkets were swapped for the real jewelry.
It's serious enough San Francisco Police commissioned a Cantonese video explaining the scam. (English explanation is below the video)
Theft Scam Targeting Older Chinese Women. (Video Re-enactment) on Vimeo