Jason Momoa's 'Heart is Broken' After Death of Close Friend

Aquaman star Jason Momoa is mourning the loss of his friend Travis Snyder. In an emotional Instagram post, Momoa paid tribute to his late friend. "We lost a warrior today. I love u travis," he captioned a series of notes that appear to have been from Snyder in preparation for his death. The caption continued, "Strongest man I ever met You are in my soul and in my bones im so grateful to have been your friend. Rest brother. What an ANGEL all my aloha to Heidi Luke Miles and my Hank Unko loves you." 

The same statement went live on Snyder's Instagram page. In a separate post of photos with Momoa and Snyder, Momoa captioned the post in part: "My heart is broken I love you brother we lost a great one Live aloha."

PEOPLE reports Snyder, who was 45 at the time of his passing, was diagnosed with acute myeloid leukemia in 2015. He was working alongside Momoa to educate people on how to become a bone marrow match/donor. The American Cancer Society notes that it's a cancer that "starts in the bone marrow (the soft inner part of certain bones, where new blood cells are made), but most often it quickly moves into the blood, as well. It can sometimes spread to other parts of the body including the lymph nodes, liver, spleen, central nervous system (brain and spinal cord), and testicles."

PEOPLE previously spoke to Snyder about his friendship with Momoa. "We met through happenstance and mutual friends after my first cancer battle in 2015," Snyder recalled. "I think in the aftermath of treatment I was very focused on living every day with purpose and my heart was open and Jason wasn't quite as busy then and he lives with such a big giving heart and aloha, we just connected instantly." Momoa referred to Snyder as his "buddy."

Snyder was the founder of The Color Run. According to the organization's website, The Color Run is a five-kilometer, untimed event where at each kilometer mark, Color Runners are doused from head to toe in a different colored powder. Participants wear white at the starting line and finish the race plastered in color. At the conclusion of the race, there's a celebratory party with music, dancing, photo ops, activity booths, vendors, and more massive color throws, which create millions of vivid color combinations.