The two young Perry boys found dead in their grandmother's van by the Lake of Isles boat launch in North Stonington Tuesday died of multiple gunshot wounds, the Office of the Chief Medical Examiner said Friday.

The cause of death for both boys was homicide. Alton Perry, 2, died of multiple gunshot wounds to the head and his 6-month-old brother Ashton died of multiple gunshot wounds, the medical examiner's office said.

The boys' grandmother, Debra Denison, died of a single gunshot wound to the head, according to the medial examiner's office. Her death has been ruled a suicide.