The woman has been identified as 58-year-old Amy Leffler.
“This is a tragic accident and we offer our thoughts, prayers and condolences to Ms. Lefflers' husband and young daughter” Pound Ridge Police Chief David Ryan said in a statement.
Police said that an investigation into the accident is ongoing but that it does not appear that any vehicles were involved.
Police said that a call was received at 6:50 a.m. on Tuesday, Sept. 20, for a cyclist who was down in a roadway, which is Old Stone Hill Road.
Two civilians were providing on-site aid to Leffler when police arrived.
Aid was then administered by police, Pound Ridge Ambulance and Westchester EMS.
Leffler was taken to Stamford Hospital, police added, and died there on Wednesday.
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