Swindlers who called people and pretended to be relatives in need of money had a success rate of roughly two out of three calls last year, bilking their victims out of some 4.3 billion yen, the National Police Agency said Thursday.

The tactic is known as the "Ore ore" ("It's me") fraud for the phrase, which suggests familiarity with the mark, the scam artist uses to begin the call. The swindlers were successful in 4,319 of the 6,504 cases, the NPA said. Most of the victims were female, and elderly.

Police arrested 58 people suspected of involvement in 179 of the cases.