Key questions in a Mississauga, Ont. homicide investigation remain unanswered after a teenage boy suspected in the murder of a 17-year-old girl died this weekend.

The teenage suspect died of injuries he sustained in a fall from a Highway 401 overpass, Peel Regional Police confirmed late Sunday on Twitter.

"The suspect in the Nijjar murder has succumbed to his injuries," the tweet read. "Homicide continues to investigate."

On Friday morning, 16-year-old Akash Wadhwa plunged to the eastbound lanes of Highway 401 from the Mavis overpass before being struck by a car.

Police had been investigating a link between that incident and their discovery of the body of a teenage girl in a small park in Mississauga later Friday.

Police were called to a wooded section of a parkette on Spinnaker Circle, in the Courtneypark Drive West and Mavis Road area, shortly after noon.

There, they found the body of a young woman with obvious signs of trauma. The victim was identified as 17-year-old Kiranjit Nijjar of Mississauga.

Const. Erin Cooper said on Monday that Wadha is the only person of interest in Nijjar's death so far.

Friends of Wadha said he and Nijjar were both Grade 12 students at Mississauga Secondary School.

Navjot Mann, who knew both teens, told CTV Toronto that the boy confided in Nijjar.

"They were best friends for a long time. They were always together, always at lunch period, they'd always be together," Mann told CTV Toronto last Friday.

Grief counsellors dispatched by Peel District School Board arrived at the high school on Monday to help students mourn.