BTS's record label sues over 'malicious' posts
Trolls who posted "insulting" and "defamatory" comments about BTS have been reported to police in South Korea.
Big Hit Entertainment, the company behind the pop band, says it is taking action over posts "that exceed the reasonable and accepted boundaries of expression and personal commentary".
The firm did not go into detail about the nature of the comments.
However, it has previously sued over claims of "sajaegi" - bulk-buying albums to inflate BTS's chart position.
Earlier this summer, the company also asked for court authorisation to seize and destroy bootleg merchandise being sold outside the band's concerts.
In a statement, Big Hit explained it routinely monitored social media and message boards for posts about its artists that contained "ill-intentioned criticism, the spreading of groundless information and personal attacks".
It has also established a hotline for fans to report offensive or defamatory content.
The company claims that police have already launched investigations into its complaints, adding: "We have responded with zero tolerance against insults and defamation against our artists.
"We emphasise that there is, and will be, no leniency or settlement with the perpetrators of these acts."
Unlike the UK, where truth is a defence against defamation charges; South Korean law allows for an individual to be punished if they make a factually-accurate statement that brings another person into disrepute.
In the wake of the #MeToo movement, there have been calls for a revision of the law, which makes it particularly difficult for victims of sexual assault to speak out.
There is no suggestion that members of BTS have been accused of sexual assault. The "Report Army" Twitter account, which helps BTS fans identify and report offensive content, suggests contacting Big Hit over death threats, trolling and offers to sell the band's personal information.
BTS, who won their first MTV Award on Monday night, are the most successful band to emerge from the K-pop scene, and recently sold out two nights at Wembley Stadium.
Earlier this month, however, Big Hit announced the septet were taking an "extended period of rest and relaxation" in order to "rest and recharge in their own personal ways".
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