Update (December 24): Carrie Fisher is currently in the Intensive Care Unit after suffering a heart attack while on board a flight on Friday, her brother, Todd Fisher, confirmed to Entertainment Tonight.

"She is in the intensive care unit, she is being well looked after," Todd told ET late Friday evening. "If everyone could just pray for her that would be good. The doctors are doing their thing and we don't want to bug them. We are waiting by patiently."

Unfortunately, Fisher admitted that the actress's overall condition is still unknown.

"We don't know. We hope for the best," he said. "We certainly do not know her condition, that's why she is in ICU. I'm sure everyone wants to speculate, but now is not the time for that."

Earlier, an out-of-context AP report perpetuated that Fisher was in stable condition.

Fisher suffered a "cardiac event" on an airplane flight from London to Los Angeles International Airport (LAX), TMZ reported on Friday (December 23).

The site said sources tell them the Star Wars actress went into cardiac arrest on the plane and Fisher received CPR on board. Paramedics rushed her to the hospital upon landing. NBC News confirmed the medical emergency occurred, and a law enforcement source deemed Fisher's condition "not good" at that time.

Actress and writer Anna Akana tweeted that she was on the same United flight as Carrie Fisher when the emergency occurred.

"Don't know how else to process this but Carrie Fisher stopped breathing on the flight home. Hope she's gonna be OK," Akana wrote. "So many thanks to the United flight crew who jumped into action, and the awesome doctor and nurse passengers who helped."

While Fisher is best known for playing Leia Organa in the Star Wars series, she's acted in many films, including When Harry Met Sally, and guested on many TV shows over the years such as 30 Rock, Frasier and Catastrophe. She's also voiced Peter Griffin's supervisor Pam on Family Guy in a recurring role since 2005. She's the daughter of Hollywood icon Debbie Fisher and singer Eddie Fisher, and Carrie's daughter Billie Lourd currently stars on Scream Queens

Fisher published her eight book, a memoir called The Princess Diarist, in November 2016 — and as the Mary Sue reported, as a writer she's also had a side career as a script doctor.

Photos From the Star Wars: The Force Awakens Red Carpet Premiere:

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