Natasha Richardson's death was indeed caused by her fall on a Canadian ski slope.
The New York City Medical Examiner's Office conducted an autopsy on the Tony Award-winning actress Thursday. She died Wednesday at age 45. The office ruled her death accidental, citing the cause as an epidural hematoma due to a blunt impact to the head.
Funeral arrangements for Richardson will be handled by New York City's Greenwich Village Funeral Home.
Richardson's husband, actor Liam Neeson, and family members were by her side when she died. Her death was announced in a statement released Wednesday evening by Neeson's publicist.
"Liam Neeson, his sons and the entire family are shocked and devastated by the tragic death of their beloved Natasha," the statement said. "They are profoundly grateful for the support, love and prayers of everyone, and ask for privacy during this very difficult time."
Richardson fell Monday at the Mont Tremblant ski resort in Quebec. She initially appeared fine and joked about the fall, but the ski patrol insisted she see a doctor. Richardson declined, the resort said in a statement Tuesday.
Thursday, ABC News learned more details about what happened between when Richardson fell and when she sought medical attention. At 12:43 p.m. Monday, the first call to the paramedics was made. An ambulance arrived at 1 p.m. and transported Richardson from the foot of the mountain to the infirmary by sleigh.
Richardson thought she was fine and didn't want to stay at the infirmary. At 1:10 p.m., Richardson signed hospital waiver paperwork and walked 300 yards to hotel along with her ski instructor. She was back in her room by 1:30 p.m.
At 2:59 p.m., paramedics received a second call for help. An ambulance showed up at the hotel exactly ten minutes later. Richardson was conscious but showing signs that made paramedics call the hematology department at the Centre Hospitalier Laurentien in Ste-Agathe, where the ambulance took her.
On Wednesday, a Canadian newspaper confirmed that an ambulance was dispatched to the resort right after the accident, but the paramedics were told they were not needed and left.
"They never saw the patient," Yves Coderre, the operations manager for the ambulance service, told the Globe and Mail. "So they turned around."
"When you have a head trauma you can bleed. It can deteriorate in a few hours or a few days," Coderre added. "People don't realize it can be very serious. We warn them they can die and sometimes they start to laugh. They don't take it seriously."
Richardson was later transferred to Hôpital du Sacre-Coeur in Montreal before being flown to New York City's Lenox Hill Hospital Tuesday, where her relatives rushed to her side.
On Tuesday night, Richardson's mother, actress Vanessa Redgrave, was seen entering the New York City hospital. So was Richardson's sister, Joely Richardson. Neeson also reportedly was by her side. Actress Lauren Bacall was photographed visiting the hospital Wednesday afternoon.
Richardson Suffered Head Injury During Ski Lesson
The Toronto Star reported that Richardson, lying heavily wrapped in blankets in an intensive-care bed, tubes covering her face, was loaded into an ambulance outside Montreal's Hôpital du Sacre-Coeur at 12:30 p.m. Tuesday, in preparation for her flight to New York.
Neeson was crouched down in the back of the ambulance watching as she was loaded, according to the Toronto Star.
Tuesday, the Mont Tremblant ski resort, released the following statement regarding her accident:
"Natasha Richardson fell in a beginners trail while taking a ski lesson at Station Mont Tremblant," the statement said. "She was accompanied by an experienced ski instructor who immediately called the ski patrol. She did not show any visible sign of injury but the ski patrol followed strict procedures and brought her back to the bottom of the slope and insisted she should see a doctor.
"As an additional precautionary measure, the ski instructor as well as the ski patrol accompanied Mrs. Richardson to her hotel," the statement continued. "They again recommended she should be seen by a doctor. The ski instructor stayed with her at her hotel. Approximately an hour after the incident Mrs. Richardson was not feeling good. An ambulance was called and Mrs. Richardson was brought to the Centre Hospitalier Laurentien in Ste-Agathe and was later transferred to Hôpital du Sacre-Coeur."
A spokesperson for the resort noted Richardson was not wearing a helmet while skiing and didn't collide with anything when she fell. Thursday, in the wake of her death, Quebec officials said they are considering making helmets mandatory on ski slopes, according to The Associated Press.
Neeson, 56, left the set of "Chloe," a movie he was filming in Toronto, and rushed to his wife's side upon learning the news.
"'Chloe' will continue with its production schedule focusing on scenes which feature other cast members," the publicist for the film said in a statement to "Entertainment Tonight." "There are some scenes with Liam Neeson which have not been completed, however, we do not feel this is the time to address that matter. Our concern is for Liam and his family at this difficult time."
Richardson had two sons with Neeson, Michael, 13, and Daniel Jack, 12.
Celebrities React to Richardson's Passing
Following the news of Richardson's death, friends in Hollywood reflected on her career and legacy.
"Tash was the warm sun in the center of a large constellation of family, friends, all of those lucky enough to know her," Meryl Street said in a statement to ABC News. "She is irreplaceable in our lives; she gave us so much, so generously -- her legacy is the love that connects us all."
Lindsay Lohan, who co-starred with the actress in 1998's "The Parent Trap," released the following statement through her publicist.
"She was a wonderful woman and actress and treated me like I was her own," Lohan's statement said. "I didn't see much of her over the years but I will miss her. My heart goes out to her family. This is a tragic loss."
Jane Fonda wrote about Richardson on her blog, saying that she met the actress on a movie set when Richardson was just a child.
"I first met her on the set of Julia [in which she starred with Vanessa Redgrave]. She was a little girl but already beautiful and graceful. It didn't surprise me that she became such a talented actor," Fonda said.
Ralph Fiennes appeared with the actress in the 2005 period drama "The White Countess."
"For everyone who knew and loved her, Natasha's death is a terrible, devastating loss. She was a star. A great actress, a beautiful woman, a fiercely loyal friend, a brilliant and generous companion. She was an adoring and loving wife and mother. She was unique. My thoughts and prayers go out to Liam and her beautiful sons, Micheál and Danny and to all her family," Fiennes told ABC News in a statement.
"I cannot imagine a world without her wit, her love, her mischief, her great, great talent and her gift for living. I loved her very much. She was a supreme friend. I shall miss her deeply."
"Natasha is irreplaceable," actress Mia Farrow said in a statement to reporters. "I cannot think of anyone kinder, more generous, thoughtful, smarter or more fun. She is the godmother of two of my children. The Neesons and Vanessa [Redgrave] have always made me feel a part of their wonderful family. My thoughts and prayers are with them."
"Natasha was brilliant, beautiful, funny, talented beyond measure, as emotionally raw as she was razor sharp," said Jodie Foster, who co-starred in 1994's "Nell" along with Richardson and Neeson. "May Liam, her beautiful boys and her loving family hold her close as they move through this tragic moment."
"She had an incredibly luminous quality, that you seldom see, and a great sense of humor," Dame Judy Dench said in a statement to reporters. "I thought she was a really great actress."
"We spent one amazing day on a boat with my whole family and she and Liam and the boys," Joan Rivers said in a statement to reporters. "They were such a family. I mean just shouldn't have happened. And they made such a good-looking couple too. He doted on what she said, she doted on -- it was just perfect."
Sam Mendes, who cast Richardson as Sally Bowles in "Cabaret," remembered her mastery of her craft.
"Natasha combined the best of Redgrave and Richardson: the enormous depth and emotional force of a great actor on the one hand, and the intelligence and objectivity of a great director on the other," he said in a statement to reporters. "She was one of a kind, a magnificent actress. She was also an amazing mother, a loyal friend, and the greatest and most generous host you could ever hope to meet. It defies belief that this gifted, brave, tenacious, wonderful woman is gone."
Richardson Part of Acting Dynasty
Richardson was a member of one of Britain's most famous acting dynasties. She was the eldest daughter of Oscar-winning actress Vanessa Redgrave, 72, and director Tony Richardson.
Her father passed away in 1991 due to complications with AIDS. She had long been a supporter of AIDS-related charities, including amfAR, on whose board she had served since 2006.
Asked to comment on her skiing accident before Richardson's death was announced, a representative for amfAR told ABCNews.com, "Our thoughts and prayers are with Natasha and her family right now. Obviously, we're very saddened and disturbed by this news."
Richardson also donated her services to God's Love We Deliver, an organization that provides fresh meals to people living with HIV/AIDS.
"Everyone at God's Love We Deliver is profoundly saddened to hear about her accident," Karen Pearl, president of the organization, said in a statement to ABCNews.com before Richardson's death. "As we hope for the best, our thoughts and prayers are with her, Liam, and their entire family at this difficult time."
Richardson's sister, Joely, stars in the TV series "Nip/Tuck."
Richardson's Rich Career
Richardson starred in many films, including "The Parent Trap," "Maid in Manhattan," "A Month in the Country," "Gothic" and "Nell." But her chief experience was in theater. She was trained at London's Central School of Speech and Drama and won a Tony Award in 1998 for playing Sally Bowles in "Cabaret." As a tribute to her, the theaters of Broadway said they would dim their lights Thursday night.
Sher met her husband in 1984 while filming the TV mini-series "Ellis Island," but their relationship didn't blossom until 1993, when they reunited on Broadway for a revival of "Anna Christie." Their on-stage chemistry was too strong to ignore, and shortly after "Anna Christie's" run, Richardson separated from her husband, producer Robert Fox. She and Neeson married in 1994.
Richardson acted with her legendary mother at multiple points in her career. In January, Richardson and Redgrave played the roles of mother and daughter in a one-night benefit concert version of "A Little Night Music," the Stephen Sondheim-Hugh Wheeler musical, on Broadway.
The two also acted alongside each other in the 1985 theatrical revival "The Seagull" and the 2007 movie "Evening." In a 2003 interview with UK newspaper The Guardian, Richardson talked about taking on the same profession as her mother.
"I don't know if I could ever put myself in the same category as her," she said. "She is one of the greatest actresses of our time, so I'm not sure I would put myself in that bracket."
She expanded further in a 2005 interview with The Independent.
"I know the pressures of being the daughter of a great actress," Richardson told the newspaper. "But it's inspiring. You learn so much that other people don't get to learn until later on. My father being a director, I learnt a real work ethic. You think: 'One day, I'd like to be as good as that.' But when I was starting out professionally, I had a level of attention put on me that I didn't deserve or wasn't ready for. And it was hard, particularly in England, to make my way. That's partly why I moved to New York, where you can be who you are for your work and not so much to do with family baggage."
But in the same interview, Richardson talked about how she didn't want her sons going into acting.
"They'd be the sons of a great actor," she told The Independent. "And that's quite a gorilla to carry on your back. This profession is very tough and not many people make it , and even if you do, then you can still get slapped in the face constantly. So I hope they do something else -- but if they're determined, so be it."
Additional reporting contributed by ABC News' Sharyn Alfonsi, Monica Escobedo, Emily Friedman, Lindsay Goldwert and Luchina Fisher.