ZURICH (Reuters) - A fraudster persuaded a 75-year-old Swiss woman to transfer 45,000 francs ($46,225) to him as a “police officer” supposedly taking part in a nationwide program to guard elderly people against telephone scams.

Last week’s incident in the eastern canton of Graubuenden was a new twist on the old trick of getting elderly people to send money to a supposed favorite grandchild in trouble, police said on Monday.

“Be suspicious of supposed police who call speaking high German,” a police statement advised residents of the region, where many speak German and Romansch dialects very different from the “Hochdeutsch” (high German) spoken in Germany.