The 60-year-old was returning to L.A. from London.
Actress Carrie Fisher, 60, reportedly suffered a heart attack on board a flight from London to Los Angeles Friday afternoon that left her in critical condition.
The Star Wars star's brother, Todd Fisher, told reporters that his sister is now being treated in intensive care.
Although he said she is receiving excellent care, he also said “It’s not fair to say (she's) ‘stable’. I am not saying she is fine, or not fine,” he told reporters. “She is in the ICU.”
The incident reportedly happened 15 minutes before 11-hour flight landed at LAX.
The plane was met by medical personnel after the pilot reportedly told control that one of the nurses on board the flight was tending to an "unresponsive passenger."
The nurse was performing life-saving measures on Fisher and she was then rushed to UCLA Medical Center once the flight landed, according to reports.
Read: Carrie Fisher Says She Was 'So Insecure' About Her Affair With Harrison Ford
After the news broke, celebrities began sending messages of love and support to the woman who portrayed Princess Leia.
as if 2016 couldn't get any worse... sending all our love to @carrieffisher
— Mark Hamill (@HamillHimself) December 23, 2016
I ask everyone to stop for a moment and send special thoughts to @carrieffisher.
— William Shatner (@WilliamShatner) December 23, 2016
Sending our love ❤ and support to the inimitable @carrieffisher right now. Please feel better soon! ?
— Katie Couric (@katiecouric) December 23, 2016
We are NOT losing @carrieffisher. Do you hear me? We are NOT losing @carrieffisher. Love you @carrieffisher.
— billy eichner (@billyeichner) December 23, 2016
Fisher was returning to Los Angeles after a book tour of her latest autobiography, The Princess Diarist. She recently appeared in Star Wars: The Force Awakens in 2015.
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