The Middlesex County Prosecutor's Office says the dog was inside a car that was driven by 49-year-old Naglaa Armanious.
Authorities say she crashed into a utility pole then hit five pedestrians who were walking from services at Young Israel in East Brunswick on Saturday.
Ari Horowitz and his wife Sari were pronounced dead at the scene.
Another couple and a 27-year-old man remain hospitalized in stable condition.
The driver was released from the hospital.
No charges have been filed and the investigation continues.