"We responded to an emergency call," LAFD spokesman Devin Gales told ABC News. We transported one patient from that location to a local hospital."
Neighbor Clare Staples told the Associated Press that she saw firefighters working to resuscitate the actress, who was on a stretcher. Murphy's husband, wearing pajama bottoms and no shoes, appeared "dazed" as firefighters tried to save her, Staples said. "It's just tragic," she added.
"They were trying to resuscitate her all the way down to the fire truck, and then they had her by the fire truck and they were obviously trying to put tubes down her throat and resuscitate her, and I think she was obviously dead at that time," Staples told KABC-TV.
Murphy's father, Angelo Bertolotti, told the Associated Press that he learned of his daughter's death from his son, the actress's brother, and was stunned. "She was just an absolute doll since she was born," Bertolotti said from his Branford, Fla., home. "Her personality was always outward. Everybody loved her - people that made movies with her, people on a cruise - they all loved her. She was just a regular gal." He said he hadn't heard much about the circumstances of Murphy's death. Bertolotti divorced her mother when Murphy was young and hadn't seen Murphy in the past few years. "She was just talented," Bertolotti said. "And I loved her very much."
Murphy got her first job in Hollywood at the age of 14, when she starred as Brenda Drexell in the series "Drexel's Class."
She then went on to guest star on television series such as "Blossom" and "Frasier."
One of her most notable roles was in "Clueless," in which she starred opposite Alicia Silverstone as the bubbly, yet naive high school student Tai Frasier eager for a makeover.
She also co-starred with Angelina Jolie in "Girl, Interrupted" and Eminem in "8 Mile."
Most recently she starred in the romantic comedy "Little Black Book" and "Sin City." Lifetime cast her in a TV movie in 2009 where she played the main character in "Tribute."
Murphy also dabbled in music. In 2006, she teamed up with the world-famous DJ Paul Oakenfold. The pair released a single "Faster Kill Pussycat" which became a club hit and hit number one on Billboard's Hot Dance Club Play chart.
After her success in "8 Mile," Murphy was cast in her first lead role in the romantic comedy "Just Married," with Ashton Kutcher, to whom she was romantically linked for a brief time.
Kutcher tweeted this morning about Murphy's death: "2day the world lost a little piece of sunshine," Kutcher wrote. "My deepest condolences go out 2 Brittany's family, her husband, & her amazing mother Sharon."
Her box office success was often marred by rumors about her wacky behavior on set.
In February of 2008, The New York Post reported she was making outrageous demands while acting "like a diva" on the set of "Across the Hall."
One witness said, "She's extremely difficult. When she gets to the set, it comes to a grinding halt. She's so hot and cold, you never know."
It was also reported that her husband Monjack would lurk around the set and intervene so much that producers had to call a meeting to discuss how to deal with him.