B-boy legend David “MexOne” Alvarado, who was influential in establishing the Red Bull BC One breakdancing competition, has passed away at the age of 35.

Red Bull BC One’s 2015 champion, Victor Montalvo, was mentored closely by Alvarado and penned an emotional Instagram tribute on Tuesday (September 19).

“Wow. Just woke up hearing my brother, my friend passed away,” he wrote. “Just want to say he is the biggest reason I did that whole winning streak in 2015, he even told me years before it would happen! Crazy. There was only 3 people who believed in me and he was one of them. I will always remember you brother, you did so much for me and for everyone in the breaking scene. me and the fam will miss you, there’s so much more I can say but I’m just out of words cant believe it. Rest in peace.”

Stance Broadcasting and Media Production Company shared a video to its Facebook page commemorating all of Alvarado’s contributions to Hip Hop culture. It documents his journey from illegal Mexican immigrant to selling b-boy DVDs out of his backpack to becoming the owner of his own company, The B-Boy Spot, to blossoming into a celebrated figure in the b-boy community.

Alvarado had recently launched his own clothing brand, Biggest & Baddest, and also established the first b-boy/b-girl college scholarship. He was endlessly dedicated to his only son. In fact, his entire Instagram account is peppered with photos of his child.

“As a kid I always had dreams, my biggest dream was to be a father to a boy,” Alvarado wrote on Facebook last year. “God granted me that dream. I vowed to be with him and guide his every day of his life. The dream was somewhat taken away when his mom and I decided to split over two years ago. It was then I decided my son wouldn’t go through the same childhood I went through. Most don’t know but I’m not with him every day. It hurts me to know he is a few miles away but might as well he be a million miles away. My time with him is precious. I devote my life to him. Everything I do is for him. Unlike me, he will have a loving and supportive father. Unlike me, he will know unconditional love.”

Although details surrounding his death remain scarce, countless people took to social media to express their condolences, including the people behind the Pro Breaking Tour, which Alvarado established.

Check out some of those reactions below.