For some 20 years, K-pop artist Kim Jae-joong has been hounded by fans stalking him to get a sneak peek into his private life.

A week ago Kim Jae-joong decided to stand up for himself and take legal measures against “sasaeng” fans -- industry slang referring to fans who invade an artist‘s private life, often exhibiting problematic and obsessive behavior.

“We are currently gathering information about Kim Jae-joong’s sasaeng fans and the private taxis they hired to stalk our artist,” Inkode Entertainment, the agency representing Kim told The Korea Herald Monday.

This comes after Kim posted a photo of private taxis hired by his sasaeng fans on his Instagram account on Jan. 22.

“These (sasaeng) fans waiting in every corner for me to come out and taxi drivers that follow me around claiming that they have no other choice than to do so as their client asks them to, have not changed a bit,” Kim Jae-joong commented on the photo.

“I have surveillance camera shots of all these six (sasaeng) taxis yesterday and will continue to collect more. I hope you get punished for collecting someone’s privacy and pain,” Kim Jae-joon added, making it public that he will take legal action against them.

“How much these taxis have contributed to stalking the artist needs to be determined. But in this case, where the taxis are helping these fans follow the artist’s official and private engagements more than once and are working in a systematic manner using walkie-talkies to communicate with one another, they are likely to face punishment by law,” said lawyer Lim Ju-hye.

Kim debuted as a member of TVXQ in December 2003 and has been followed around by obsessive fans ever since.

His agency added that they suddenly disappeared after Kim declared a legal war against them, and that they now refrain from waiting for the artist outside the agency or his house.

Kim is not the only K-pop artist with problem fans.

K-pop sensation BTS have suffered from obsessive fans who sent deliveries and letters to members‘ homes, even breaking into them in some instances.

Big Hit Music took the matter into its own hands by filing criminal complaints over stalking and home invasion.

“It is true that the fandom culture has played a big role in making K-pop beloved by many around the world. But these malicious practices must be eradicated for further expansion of the K-pop industry,” said Hybe in an official statement released last December.

Members of the K-pop boy group NCT also have fans who follow them around to take photos of them or touch them and call them on their private phones non-stop.

In November 2022, a fan entered the home of Haechan of NCT and his family. Jaehyun, also of NCT, had a fan break into the hotel room where he was staying during the group‘s US tour in October 2022.

SM Entertainment, which represents NCT, made the incident public to reveal the seriousness of the infringement on artists‘ privacy and to warn fans against such behavior.

The K-pop powerhouse announced in August last year that they are taking legal action against obsessive stalking by fans.

Industry sources point out the need for heavier punishment of sasaeng fans because the punishments they receive are not strong enough to act as a deterrence.

“It‘s a crime when you make someone suffer either physically or psychologically through your actions which derive from the feeling of your liking. The law states that texting, calling them, and following someone to their house without their consent can be punished as stalking,” said lawyer Lim.

Stalking can result in up to three years in prison or a fine of up to 30 million won ($22,500).