"To everyone who cares about me and my team, hello. This is Key," he posted to Instagram earlier today. "I don't know how to say this, but.. I wasn't able to participate during the Japanese promotions on the 24th due to personal problems. My grandmother passed away on the 23rd. She took care of me with love when I was growing up, so I am still in shock over the fact and can't believe that she is gone."

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"However, I felt that it was wrong to tell this news through a company announcement ahead of SMTOWN and the first concert of the tour, so I am just telling you this now. I know that my grandmother was watching me from heaven and will continue strongly through the rest of the tour," he said. "Please support me and I will see you with a smiling face! Thank you."

May she rest in peace and our thoughts are with Key and his family during this difficult time.