She was 60 years old.
"It is with a very deep sadness that Billie Lourd confirms that her beloved mother, Carrie Fisher, passed away at 8:55 this morning," Halls said in a statement. "She was loved by the world, and she will be missed profoundly."
Fisher's mother, actress Debbie Reynolds, wrote on her Facebook page, "Thank you to everyone who has embraced the gifts and talents of my beloved and amazing daughter. I am grateful for your thoughts and prayers that are now guiding her to her next stop. Love Carrie's Mother."
And Harrison Ford, who played Han Solo in "Stars Wars," said in a statement Tuesday, "Carrie was one of a kind … brilliant, original. 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."
Fisher was rushed to the hospital after going into into cardiac arrest while aboard a flight from London to Los Angeles on Friday.
Just last month, in an interview with Rolling Stone magazine, Fisher was asked if she feared death.
"No. I fear dying," she said. "Anything with pain associated with it, I don't like. I've been there for a couple of people when they were dying; it didn't look like fun. But if I was gonna do it, I'd want someone like me around. And I will be there!"
Earlier in the Rolling Stone interview, she said, "I'm not going to enjoy dying, but there's not much prep for that."
She came from Hollywood royalty: She was the only daughter of Reynolds and singer Eddie Fisher. Following in her famous parents' footsteps, Carrie Fisher made her Broadway debut at the age of 15 alongside her mother in "Irene." Her movie debut came in the 1975 Warren Beatty film "Shampoo," and in 1977, "Star Wars" made her a household name.
After she appeared in a variety of TV roles, her next big movie was "The Blues Brothers," though she was listed in the credits as "mystery woman." She then appeared in the "Star Wars" sequels "The Empire Strikes Back" and "Return of the Jedi" and starred in the Broadway show "Agnes of God." In 1986 she appeared in Woody Allen's acclaimed film "Hannah and Her Sisters."
The next year saw the arrival of her first book, "Postcards From the Edge," a loosely autobiographical novel, which was turned into a film starring Meryl Streep and Shirley MacLaine. Fisher continued working steadily, appearing in movies like "When Harry Met Sally," "Austin Powers: International Man of Mystery," "Scream 3" and "Jay and Silent Bob Strike Back." Her career as an author continued as well, with the novels "Surrender the Pink" and "Delusions of Grandma."
She was a top Hollywood script doctor, polishing other writers' screenplays. Among the movies she worked on: "Hook," "Lethal Weapon 3" and "Outbreak."
Fisher, who struggled with drug addiction and bipolar disorder, received an Emmy nod for her work in an episode of "30 Rock," and she mounted one-woman plays and published more books, including 2016's "The Princess Diarist."
Her acting career was revitalized with her return as Leia in 2015's "The Force Awakens," in which we learn that Leia and Han Solo have split up and that their son Ben, aka Kylo Ren, has turned to the dark side of the Force.
Fisher was married to Paul Simon from 1983 to 1984; they had no children. She and talent agent Bryan Lourd welcomed a daughter, actress Billie Lourd, in 1992.
Fisher is survived by her daughter, mother, brother and half-sisters Joely Fisher and Tricia Leigh Fisher.
ABC News' Lesley Messer and David Caplan contributed to this report.