Natasha Richardson died due to "epidural hematoma due to blunt impact to the head," the New York City Medical Examiner's office announed on Thursday.
Medical Examiner Ellen Borakove released a statement Thursday saying the actress' death was ruled "an accident." Time of death was determined to be 7:26 PM on Wednesday, March 18.
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The autopsy was preformed at NYC Medical Examiner's Office.
As previously reported on AccessHollywood.com, the star of stage and screen died Wednesday after suffering a serious head injury on a Canadian ski slope on Monday.
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Richardson's accident occurred at Station Mont Tremblant near Montreal while the Tony-winning star was taking a skiing lesson.
Upon news of the accident, Richardson's husband, Liam Neeson, who was filming the movie "Chloe," in Toronto, rushed to his wife's side.
On Tuesday, Richardson was flown to the Lenox Hill Hospital in New York City, where family and friends gathered, including sons Micheal Richard Antonio, 13, Daniel Jack, 12, sister Joely Richardson, mother Vanessa Redgrave and aunt Lynn Redgrave.
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Neeson and her family released a statement on Wednesday afternoon to Access Hollywood confirming the news.
"Liam Neeson, his sons, and the entire family are shocked and devastated by the tragic death of their beloved Natasha," the statement read. "They are profoundly grateful for the support, love and prayers of everyone, and ask for privacy during this very difficult time."
A service is planned for the actress at the Greenwich Village Funeral.
Richardson was 45.
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