jimmy rich/ Instagram Robert Downey Jr. and Jimmy Rich
Downey, 56, shared news of the "terrible and shocking tragedy" on his Instagram feed Thursday alongside a carousel of images of Rich, revealing that Rich had been in "a fatal car accident" around 8 p.m. Wednesday.
"He was a brother, my right hand man, an uncle to our kids and beloved by all who experienced his singular character and wit," the actor continued. "Our thoughts go to his relatives, friends, co-workers, and all the fans who knew him as the man who supported every step of my recovery, life and career."
"Again, my condolences to his beautiful family, and the legacy of hope and redemption his life will continue to represent," Downey wrote, concluding, "Peace Be Unto You."
Rich first served as Downey's assistant on the set of 2003's The Singing Detective. The two would go on to work together over 20 more times, including on all of Downey's Marvel films, according to Rich's IMDb page.
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Robert Downey Jr./ instagram Josh Brolin and Jeremy Renner's comments on Robert Downey Jr.'s Instagram post
Robert Downey Jr./ instagram Chris Pratt and Mark Ruffalo's comments on Robert Downey Jr.'s Instagram post
"Wow. Brother. What a devastating loss," wrote Renner, 50, while Brolin, 53, offered, "No words. Just tears and gratitude for the gift that was him."
"Oh no! 😢 I'm so sorry man. Im praying his family, you and yours," added Pratt, 41. "That sucks so bad. I'm so sorry to hear that. He was awesome. Such a tragedy."
"Such a tragedy. Such a good man," wrote Ruffalo, 53. "I have known him almost as long as I have known you, Robert. Breaks my heart to have Jimmy go over to the other world. You will be missed Jimmy. Thanks for always being real, always being there to lend a hand and showing the way of light forward to so many people. Another sad day."
"Jimmy Rich was unlike anyone else," wrote the Captain America: Civil War star, 39. "He left an indelible impression on everyone he met. No one more so than my brother @robertdowneyjr They were inseparable."
After saying he was "sending all my love to Jimmy's friends and family," Evans added, "Be sure to hug your loved ones tightly and please take the time today to show Downey how many people love him and are here for him during this incredibly dark time."