An elderly woman helped her granddaughter avoid falling victim to a voice-phishing scam, police said Wednesday.

Police say a woman received a call Sept. 7 from a person claiming to be a prosecutor from Seoul. The caller told her that she had been involved in a money-laundering scam, the police said, and convinced her to move her money to a “safe” bank account. The caller even sent her what seemed to be official documents and photos of a suspect under arrest to make the story sound believable.

Believing what the caller had told her, the woman withdrew 13 million won ($11,600) from her savings account.

But the woman’s grandmother noticed how long she had been on the phone in her locked bedroom and grew suspicious that it might be a voice-phishing scam. She immediately told her son and asked him to report it to police.

The woman initially did not believe her grandmother or her father, but was finally convinced when the police came.

The elderly woman had received education about voice-phishing scam prevention a few days before the incident, police said.

Gangneung Police said they would increase the frequency of their education programs, as they were proving to be effective.

(jeeminkim@heraldcorp.com)