Kim Jeong-Hwan, the singer and performer known to K-pop fans as Yohan, has died. A member of popular group TST (formerly known as Top Secret), Yohan was 28 when he died earlier this week, as confirmed by the band’s label, KJ Music Entertainment. A cause of death has yet to be reported.

Per People, Yohan was originally a member of the boy band group NOM, before debuting with Top Secret when it was launched in 2017. Although they scored modest successes with two albums in 2017, the group re-branded in 2018 as TST; they released their latest single, “Countdown,” in January of 2020. As with many K-pop entertainers, Yohan was active on social media, vlogging with fans and posting frequently on Instagram.

In its statement about his death, KJ Music Entertainment specifically asked that “media articles about Yohan’s passing, such as those making speculations about the cause of his death, be refrained out of respect.” The Korean entertainment industry has seen a number of deaths among its young performers in recent months; many of them have been either reported as, or confirmed to be, the result of suicide.