The US Justice Department said Thursday some two million elderly Americans have been deprived of $750 million in various rackets over the last year, including fake technical support scams conducted from Indian call centers.
The fraud has led to 255 indictments in the US but officials say the targeting of seniors is a global problem, with victims in Britain, Canada and Germany.
Growing technical support fraud has been among the most worrying causes for complaint, with 142,000 US consumers claiming to have been victims in 2018, among them a large number of elderly.
In the classic scenario, a window opens on a victim's computer and says there is a technical problem, accompanied by a number for a technical assistance center.
The message seems to come from an actual company, such as Microsoft, but the number is for a call center, often based in India.
Once the victim makes the call, their contact offers to take control of their device remotely and says they have detected the presence of a virus or other problem, then proposing to fix it immediately and install security software for a fee.
The victims are then referred to accomplices in the United States who are responsible for collecting the money and sending it abroad. In the past 12 months, 600 of these accomplices have been identified by US authorities.
The Justice Department did not say how many people had been arrested over the scams, nor their nationality, but gave the example of two Indians charged this week in California for recruiting an accomplice.
"We look forward to working with law enforcement in India to encourage more collaboration and action on the ground and in the courtroom to ensure these schemes stop," a senior Justice Department official said.
Another type of scam involves sending letters that promise lottery winnings or other turns of good fortune.
A 56-year-old French-Canadian, Patrice Runner, was arrested in Spain and charged with a scam of that type that lasted more than 20 years: he sent letters in the name of famous French fortune tellers, vowing to guarantee them wealth if they paid him money.