Niagara police Insp. Jim McCaffery says investigators are reviewing 50 local missing person cases but none so far have matched the description of the dismembered victim.
"We ask that you contact female family members that you have not heard from recently," said McCaffery during a news conference Tuesday at Niagara Regional Police headquarters in St. Catharines, Ont.
"Contact co-workers who have not shown up to work to check on their welfare and check on neighbours with unexplained absences," McCaffery said.
He urged the public to call the police if anything suspicious crops up.
"No tip is too small for us to follow up on," said McCaffery. "Someone in the community knows who this person is."
Police have classified this case as a homicide investigation. Over the weekend, investigators received 15 to 20 tips from the public ranging from reports of suspicious items and strange behaviour from people.
None of them have panned out, said McCaffery.
New York State police Capt. Steven Nigrelli says they have also been checking missing person reports south of the border.
Post-mortem results indicate the torso belongs to a Caucasian woman between 31 and 55 years old. The woman also had a pierced navel and two caesarean section scars.
It's believed the torso had been in the water for four to 10 days before it was found by a passerby last Wednesday.
Investigators say this case is not connected to the slaying of a Toronto woman whose dismembered remains turned up last month in Mississauga and Toronto.
Those body parts belonged to 41-year-old single mother Hua Guang Liu.
Her estranged boyfriend, Chun Qi Jiang, has been charged with second-degree murder in connection with the death and he is scheduled to appear in court later this month.
— by Linda Nguyen in Toronto
Note to readers: This is a corrected story. A previous version misspelled Liu's name.