Carrie Fisher suffered a massive heart attack Friday while aboard an airplane.
The 60-year-old actress was on a flight from London to Los Angeles International Airport when she went into cardiac arrest. Fellow passengers, including a nurse, then assisted her, according to air traffic control.
A source close to Fisher tells ET that as the plane was descending into LAX, Carrie was awakened and "she started throwing up and saying she couldn't breathe. They rushed her to the hospital and they are monitoring her heart right now."
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Officer Hernandez with airport police tells ET that officers responded to an incident at 12:15 p.m. regarding a female victim who went into cardiac arrest. When police arrived, LAFD was already performing CPR on the victim. The victim was then transported to a local hospital for further treatment.
In a statement to ET, Los Angeles Fire Department spokesman Erik Scott said they responded to LAX for a patient on an inbound flight in cardiac arrest. LAFD firefighter paramedics were standing by for the plane's arrival, provided advanced life support and aggressively treated and transported the patient to a local hospital.
Fisher was on a United Airlines flight. The airlines tells ET that medical personnel met United flight 935 from London to Los Angeles upon arrival on Friday after the crew reported that a passenger was unresponsive. "Our thoughts are with our customer at this time and any requests for additional information should be directed to local authorities," United Airlines said in a statement.
According to an eyewitness at Fisher's book signing in New York City on Nov. 23 for her memoir, The Princess Diarist, the actress looked "healthy," and was "upbeat, energetic and in great spirits" just one month ago.
Meanwhile, Fisher’s sister Joely, who is currently starring as Carabosse in Sleeping Beauty at the Laguna Playhouse in Laguna Beach, California, will not be performing her scheduled show on Friday night, ET also confirms. There is a show scheduled for Saturday, but it’s currently unknown if she will be there.
Fisher was in London filming the latest season of the U.K. comedy Catastrophe.
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She also has been busy promoting her new memoir, The Princess Diarist,which was released last month.