( CNN ) -- Toronto police made a gruesome discovery Wednesday when they opened a suitcase that two boaters on Lake Ontario had towed back to shore . Inside was a badly decomposed human torso , its gender unknown . Investigators are in touch with two other police departments investigating the recent discovery of body parts in their jurisdictions , said Toronto Det . Leslie Dunkley . `` It is a very serious case and a very serious incident and we are going to do our best to get to the bottom of it , '' Dunkley told reporters Wednesday afternoon . The floating suitcase was spotted 1.5 miles offshore and was brought to Bluffer 's Park , police said . A post-mortem examination is scheduled for Thursday . Authorities have been investigating the death of Guang Hua Liu , whose body parts were found in mid-August in several places . The investigation began along the Credit River in Mississauga , west of Toronto . Liu 's torso is still missing . CNN affiliate CTV said Liu , 41 , was a Canadian citizen of Chinese descent who once owned a spa in Toronto . She lived in Scarborough and was the single mother of three . Peel Regional Police , near Toronto , last week said an arrest was made in Liu 's death . Wednesday 's discovery of the suitcase came one week after a woman 's torso was found in the Canadian portion of the Niagara River . Niagara Regional Police said the unidentified white woman , likely in her mid-20s to early 40s , was a homicide victim . The torso was recovered near the Rainbow Bridge close to Niagara Falls . The Niagara River case is not related to Liu 's death , police have said . The Niagara River connects Lake Erie and Lake Ontario . Police try to ID dismembered body found in Niagara River .
Police in touch with other departments . Torso of Toronto-area woman is missing . Boaters on Lake Ontario in Canada bring a suitcase to shore . The suitcase contains human remains , police say .