Human remains were discovered by a worker under contract to the city who was clearing trees along the Assiniboine River in Brandon on Tuesday.
Police were called at about 7:30 p.m. by an equipment operator who said he found a body in an area near 26th Street North along the riverbank.
Officers confirmed the human remains and members of the forensic identification unit were called in, along with the criminal investigation unit.
Sgt. Mike Pelechaty, spokesperson for the Brandon Police Service, said it is not believed the remains were there for a long time, historically speaking.
"It's entirely possible the remains may be as recent as before the [winter's first] snowfall. However, until we recover the remains we won't know for sure," he said.
Most of the body is still under snow, so police are securing the area until a mobile shelter can be set up. That will allow the snow to be thawed and the body eventually removed, police said.
No other information, such as the gender of the remains, has been released.