Mark Hamill Remembers Carrie Fisher 

Mark Hamill is mourning the loss of Carrie Fisher, his on-screen sister in the iconic

“It’s never easy to lose such a vital, irreplaceable member of the family, but this is downright heartbreaking. Carrie was one-of-a-kind who belonged to us all – whether she liked it or not,” Hamill, who portrayed Luke Skywalker, tells PEOPLE following Fisher’s death on Tuesday.

“She was OUR Princess, damn it, and the actress who played her blurred into one gorgeous, fiercely independent and ferociously funny, take-charge woman who took our collective breath away,” Hamill, 65, continued.

“Determined and tough, but with a vulnerability that made you root for her and want her to succeed and be happy. She played such a crucial role in my professional and personal life, and both would have been far emptier without her,” he added.

Hamill concluded his statement: “I am grateful for the laughter, the wisdom, the kindness and even the bratty, self-indulgent crap my beloved space-twin gave me through the years. Thanks Carrie. I love you, MH.”

The actress, best known for her role as Princess Leia, was aboard an 11-hour flight from London to Los Angeles on Friday when she went into cardiac arrest. Paramedics removed her from the flight and rushed her to UCLA Medical Center, where she was treated for a heart attack. Fisher died in the hospital on Tuesday morning. She was 60.

— Mark Hamill (@HamillHimself) December 27, 2016

Hamill, who also tweeted about Fisher’s death, was not the only

costar to express sadness. Harrison Ford remembers Fisher as “one-of-a-kind…brilliant, original” in his statement to PEOPLE.

“Funny and emotionally fearless.  She lived her life, bravely…My thoughts are with her daughter Billie, her mother Debbie, her brother Todd, and her many friends. We will all miss her,” said Ford, who played Han Solo in the sci-fi franchise.

Peter Mayhew, Anthony Daniels and Billy Dee Williams were also among the

director J.J. Abrams and the film’s stars Lupita Nyong’o and Andy Serkis also tweeted tributes.

Fisher will appear one final time in her iconic role – even after her death. The mother of one had already finished filming scenes for the next

, with Hamill also set to star. The next installment is slated for a December 2017 release.

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