The medical examiner has ruled the death a homicide.
“We do not believe that this was a random act of violence,” RCMP Insp. Jerry Scott said Friday.
The victim was described as an Alberta man in his 50s.
Police wouldn't say how the man died or whether his death could be drug- or gang-related, but called the crime "horrendous."
The headless body of a man was found Saturday near Ranfurly, about 140 kilometres east of Edmonton, on the Yellowhead Highway between Vegreville and Vermilion.
A woman then found a head while she was walking in a northeast Edmonton neighbourhood on Wednesday.
"I don't know the reason why the head was in Edmonton and the body was near Vermilion," Scott said.
Some residents of Ranfurly have said the body was found lying in a ditch next to a running pickup truck.
Edmonton police say they have handed the investigation over to the RCMP.