The lead singer for South Korea’s top boy band SHINee died on Monday after being taken to hospital unconscious, Yonhap news agency reported. He was 27. Kim Jong-hyun’s death was an apparent suicide, police said. Kim, better known by his stage name Jonghyun, was found at a rented flat in Cheongdam-dong, southern Seoul, around 6:10pm, according to Yonhap, quoting police. News channel YTN reported that the singer had checked into a serviced residence for two nights. The agency said Kim’s sister made the initial call to emergency services at 4:42pm, saying she believed her brother was committing suicide. Yonhap said Kim’s sister had received a text message from her brother soon before his death that said: “Please let me go. Tell me I did well. Final farewell.” The singer was taken to a nearby hospital but later died, police said. Investigators said they discovered brown coal being burnt on a frying pan upon arriving at the flat and are looking into the circumstances of his death. The five-member boy band have become one of the country’s most popular since releasing their debut album, The Shinee World , in 2008. In 2011, SHINee made a successful foray into the Japanese market, and have since built a huge fan base there. The Japanese-language version of their single Replay sold more than 100,000 copies in Japan – at the time, this was the highest number of sales in the country for a debut single by a South Korean group. SHINee are considered among the best live performers in K-pop and have won multiple awards for their complex dance routines. Kim, who also had a successful career as a solo singer-songwriter, last appeared in public at a solo concert in Seoul earlier this month. Grief-stricken fans and fellow celebrities took to social media to express their sorrow. A Twitter account devoted to K-pop photos said: “Sending our deepest condolences to SHINee Jonghyun and those who known him well. If you’re going through a hard time, please do know that you never walk alone. Talk to someone and take care of yourself.” Another Twitter user wrote: “today we lost one of the most talented artists in korea. i’m heartbroken and devastated by the news.” my mom took these photos in march of this year when we went to shinee world together. i love you jonghyun and thank you for everything pic.twitter.com/geqWdl2tBZ — alana (@mewxing) December 18, 2017 <!--//--><![CDATA[// ><!-- //--><!]]> SHINee Jonghyun's reported final texts to his sister "It's been really hard up until now. Send me off please. Tell everyone I've suffered. This is my last greeting." https://t.co/7vGR93sDm4 — mes #TeamPinky (@OH_mes) December 18, 2017 <!--//--><![CDATA[// ><!-- //--><!]]> Media reports & Gangnam Police have confirmed that #SHINee 's Jonghyun passed away en-route to the hospital after being found unconscious in his officetel, possibly due to carbon monoxide poisoning. Our deepest condolences to his family and friends. #김종현 #샤이니 pic.twitter.com/inXTmNCLil — KOREA.COM (@KoreaDotComKR) December 18, 2017 <!--//--><![CDATA[// ><!-- //--><!]]> i dont know him yet my heart is aching. for his family. for shinee. for shawols. and especially for jonghyun, he was so helpless he thought the only way that could end his pain and suffering is by ending his life. im praying he's in a better place now. im praying he's at peace. — reese (@hestylesftmin) December 18, 2017 <!--//--><![CDATA[// ><!-- //--><!]]> Additional reporting by The Guardian