Initial autopsy results of an eight-year-old Montreal boy found dead in Vermont indicate he died from drowning, according to a report Wednesday.

The Burlington Free Press in Vermont reported the autopsy findings on the boy, who was last seen with his mother entering the U.S. Monday evening at Rouses Point, N.Y.

Police divers found his body in Lake Champlain, Vt., Tuesday evening, about eight metres from shore.

Vermont authorities found the mother and her car earlier in the day on a lot in the town of Isle La Motte, located on an island in Lake Champlain.

Richard Hill told reporters Wednesday about the shock of finding the car on his property.

"I saw blood in strange places on the doorknob on the outside of the doorknob, there was blood spatter on the inside of the windshield and on the inside of the driver's side window," said Hill.

The 48-year-old woman was transferred to hospital with what were initially described as life-threatening injuries, but her condition has improved.

State attorney David Miller said Wednesday she will be arraigned on murder charges in a matter of days.

Montreal police spokesman Robert Mansueto said the woman and the child were reported missing Monday by the woman's husband.

He said Wednesday an Amber Alert was not necessary under the circumstances.

"Two of the very important criteria is the child first has to be kidnapped, which was clearly not the case," said Mansueto. "And secondly, we have to have sufficient reason to believe that the child's life was in imminent danger, which wasn't the case."

Montreal family lawyer Maria Battaglia told CBC News that parents who are travelling alone with a child across the border should always carry a note from the other parent authorizing the travel.

She said border guards should be asking for proof, but rarely do.

With files from the Associated Press