A deceased woman found in a west-end laneway on Wednesday was not murdered, police have confirmed with CityNews.

"This is not a homicide investigation," Const. Tony Vella said Thursday after receiving results from a post-mortem examination. "It's classified as a suspicious death investigation."

"We are not releasing the cause of death."

Investigators have identified the victim, but aren't releasing her name to the public. She is 31 years old.

A passerby found her body rolled up in a rug in a laneway on Clendenan Avenue in the Dundas Street and Runnymede Road area of the Junction.

The homicide squad has now turned the case over to 11 Division.

No arrests have been made and police haven't explained how the woman ended up rolled up in a rug.