The victims -- Cornelius Dennis, 86, and Joan Dennis, 85, of Skytop Drive in Croton-on-Hudson -- were discovered on Saturday, May 26.
Initial investigation suggests the two returned home, and inadvertently left the vehicle running in the garage, according to state police. A buildup of carbon monoxide is thought to have led to their deaths on Wednesday, May 23, state police said.
The victims were discovered after a neighbor noticed three days of newspapers outside the residence.
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