The accident occurred just before 8 a.m. and involved a gray Jeep, a white cargo van and a red sedan, State Police said.
Route 9 will be closed for an extended period of time while the State Police Accident Investigation Unit reconstructs the accident, according to State Police.
Anyone who witnessed this accident is asked to contact Investigator Sean J. Morgan or Trooper John R. Kehoe the New York State Police at Cortlandt at (914) 737-7171.
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