IE 11 is not supported. For an optimal experience visit our site on another browser.

'So You Think You Can Dance' star dies at 33, and celebs are posting touching tributes

Dancer and choreographer Serge Onik competed on the show in 2014.
FOX's "So You Think You Can Dance" - Season Eleven
Serge Onik, 26, in a photo from "So You Think You Can Dance" season 11.FOX Image Collection via Getty Images

Celebrities in the dance world are mourning the passing of dancer and choreographer Serge Onik.

Onik was best known for competing on season 11 of "So You Think You Can Dance" in 2014, and he also worked as a choreographer on "Dancing with the Stars." He died of an unknown cause at age 33.

Onik's rep, Jim Keith, president of The Movement Talent Agency, confirmed Onik's death in a statement to TODAY.

"He was an amazing dancer with a huge heart and he touched the lives of everyone who met him,” said Keith. "He will be truly missed. This is a sad day for us at the agency and for the dance community as a whole. Our thoughts and prayers go out to his friends and family at this time."

"DWTS" pro Peta Murgatroyd shared her grief over Onik's passing in an emotional post Wednesday on Instagram. (Warning: Murgatroyd's post contains profanity.)

Next to a slideshow of photos of Onik, who was born in Kharkiv, Ukraine, and relocated to the U.S. when he was 3, Murgatroyd wrote, "My Serge… Koala I can’t believe it, I am completely broken."

She went on to say that she regretted not texting Onik to tell him last week that she was missing him. "My heart f------ hurts, my eyes f------ hurt and my soul is aching to squeeze you one last time. I just need one last squeeze and one last play fight like we used to.

"I just need one last giggle about something smutty and one last eye roll and maybe one last dance in the club," she continued, adding, "While I couldn’t write anything these past few days, the pain was too bad, I read all the beautiful messages from hundreds of people around the world. YOU WERE SOOOO LOVED ... SOOOO LOVED, much more than you knew. You were so kind, so jolly and were the life of the party."

Murgatroyd also recalled Onik's kindness to her after she gave birth to her son, Shai. Murgatroyd welcomed Shai with husband Maksim Chmerkovskiy in January 2017.

"There are so many memories I will cry over until I see you again,” she wrote. "But I will never forget your graciousness of helping me after giving birth to Shai. You made me dance, made me move and made me get up and believe I could do it again. I was HUGE and you told me I looked amazing haha and to not be so hard on myself. For that, I can never write/say anything that would amount to the level of gratitude I have for you. Your selflessness was unmatched."

Murgatroyd also posted two short throwback videos of Onik, who most recently appeared as a dancer in director Jon M. Chu’s "In the Heights."

"DWTS" pro Val Chmerkovskiy mourned Onik in his own tribute, writing, "Can’t believe I’m actually writing this. I love you Serge. You had this ease about you, this kindness, this love and excitement for life and the people around you. You made every moment you were a part of better.

"No words will truly describe the quality of human you were to me how much you loved me and how many times you were there for me in every and any capacity. I love you! I already miss you. I already feel just that much emptier," he continued.

Chmerkovskiy went on to describe his close friendship with Onik. "We grew up together. We moved and lived together. And as life separated us a few degrees recently every time we’d connect catch up it felt like we never missed a beat. Our friendship was unconditional. No hidden agendas, never."

Chmerkovskiy wrote that Onik "never wasted a moment to lift someone’s spirits," "saw the best in people" and tried his best "to bring joy to all of them."

"You were a real friend," he added.

Elena Grinenko, a former "DWTS" pro, shared a throwback photo on Instagram of her and Onik when they were younger. Next to the pic, she wrote, "RIP @sergeonik. We (sic) going to miss you."

Grinenko added, "I’m so sad that world lost such an amazing person like you."