Smartphones and social network services, including Facebook, are allowing perpetrators of revenge porn to take photos, post them online and share them easily, experts say, adding that people should be careful in revealing private information or photos on the Internet.
Experts warn that it is nearly impossible to delete images uploaded on websites overseas.
"People should avoid situations where they can be secretly photographed or refrain from posting private information and photos that lead to identifying (victims)," said Masashi Yasukawa, 49, head of a Tokyo-based group that offers counseling to revenge porn victims.
In one case, a woman's sexually explicit photos were posted online, she was identified from other images and the photo in question then spread along with her private information. She was engaged to be married but the incident eventually forced to cancel the engagement.
In many cases, shut-ins, or hikikomori, and those who refuse to go to school, send their photos to people whom they only know via the Internet, according to Yasukawa.
"It's because they are lonely and the fact that they don't know each other face to face (that) allows them to take bold measures," he said.
The National Policy Agency said Thursday it had learned of 68 revenge porn cases involving those who are or used to be in a relationship. The second highest category had to do with people who only knew each other online, which accounted for 14 cases.
Yasukawa warned that many teenagers fail to consult with police or even their parents, indicating the statistics are "just the tip of the iceberg."
On Monday, police arrested a 22-year-old college student from Sapporo for allegedly uploading three naked photos of his former girlfriend, 22, on his Twitter account on Jan. 19.
Police had been investigating the case after the victim filed a complaint.
