NEW ANNAN, P.E.I. - Two people are dead following a mysterious incident by the side of a Prince Edward Island highway Sunday afternoon.

RCMP Sgt. Andrew Blackadar said the body of a 36-year-old woman was found inside a vehicle stopped on the shoulder of Highway 2 in New Annan shortly before 4 p.m.

A 47-year-old man behind the wheel was injured but died later in hospital.

Blackadar said investigators don't know yet what occurred.

"At this point, I can certainly say the death of the female is suspicious and now we're certainly treating the death of the male as suspicious," he said.

Blackadar said investigators were trying to determine the events leading up to the discovery, which was made by another motorist who then called police.

"We're also trying to determine if the (woman's) death occurred here on the highway or if something happened before that, but we're not quite sure of that yet."

Blackadar said the motorist stopped to help after seeing the vehicle on the side of the road with its four-way flashers blinking and the driver's door wide open.

"The motorist felt that the male in the driver's seat was in some sort of distress and that's what caused him to pull over and investigate further," he said.

The names of the man and woman were not released.