Robert Downey Jr. was joined by several of his Marvel pals in paying tribute to Jimmy Rich, RDJ's personal assistant who died unexpectedly in a tragic accident. On Wednesday evening, Rich was in a fatal car accident, though additional details are currently unknown. In a post on Instagram, RDJ included an image of Rich along with a message of tribute for his late friend, and it's clear that the actor is in tremendous pain over the surprising loss.

"This is not news. This is a terrible and shocking tragedy," Robert Downey Jr. writes. "Jimmy Rich was in a fatal car accident at approx. 8pm yesterday. He was a brother, my right hand man, an uncle to our kids and beloved by all who experienced his singular character and wit.. 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."

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The Iron Man star adds: "Again, my condolences to his beautiful family, and the legacy of hope and redemption his life will continue to represent. Peace Be Unto You."

On the post, various famous friends of RDJ have joined the actor in paying tribute to Jimmy Rich. Downey's The Avengers co-star and Hulk actor Mark Ruffalo said, "Such a good man. 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."

Thanos actor Josh Brolin added: "No words. Just tears and gratitude for the gift that was him."

"Wow. Brother. What a devastating loss," said Jeremy Renner, who plays Hawkeye.

Oh no! I'm so sorry man," says Guardians of the Galaxy star Chris Pratt. "Im praying [for] his family, you and yours. That sucks so bad. I'm so sorry to hear that. He was awesome. Such a tragedy."

Chris Hemsworth, who plays Thor in the Thor and Avengers movies, also wrote: "So sorry mate. Absolutely Heartbreaking. Such a wonderful human. He'll be missed."

And Gwyneth Paltrow, who's been appearing alongside RDJ in the MCU since the very first Iron Man movie, also said, "Please no oh my god."

Other celebrities have also been saying some kind words about Rich in the wake of his death. Deadpool actor Ryan Reynolds, who will join the MCU soon enough with Deadpool 3, said to RDJ: "So sorry to hear this. Condolences to you and Jimmy's family. Heartbreaking."

"So truly sorry for this incredibly difficult loss," Josh Gad said as well. "Sending lots of love to both Jimmy's family and you."

Jack Black also sums up what a lot of people are feeling by writing, "Heartbroken. Such a good man."

Rich was just 52 years old. At this time, we offer our condolences to the family and friends currently in mourning. May his memory live on as he rests in peace. This news comes to us from Robert Downey Jr. on Instagram.