Toronto police hope to scour for clues the computer of a Chinese man who witnessed via webcam the final moments of a student found dead last week.
Hours before Qian Liu was found dead on Friday, a friend in China chatting with her online saw her struggle with an intruder who came to the door.
Detectives are investigating the 23-year-old’s death as a homicide.
They are searching for her laptop, webcam and phone, believed taken from her apartment by the intruder.
Detectives have interviewed a “person of interest” but declined to say whether he was the intruder seen online.
Police have yet to determine a cause of death.
“Liu’s death has not been classified as a homicide,” Toronto police Sgt Frank Skubic told reporters on Tuesday, describing the York University student as “hard-working”, with a small circle of friends.
“We are investigating this as a homicide and with the due diligence that’s required of a homicide investigation… with the expectation that at some point we will be able to come to a determination as to what led to her death.”
According to police, Ms Liu and a male friend were chatting at about 0100 local time (0500 GMT) when a man unknown to the friend knocked on the door asking to use Ms Liu’s cell phone.
She let him into her basement flat and a struggle ensued for several minutes while the friend watched in horror, police said. Then the intruder shut the IBM laptop, apparently taking it and the attached webcam with him when he fled the apartment.
The friend then sought frantically to alert authorities in Canada. Ms Liu was found dead on Friday morning after a Chinese consulate official contacted police.
The web video chat was streaming live between the computers in Canada and China, Sgt Skubic said, and investigators are working with computer experts to determine if any “artefacts or remnants” of the chat remained on the friend’s computer that could provide a clue.
Officers who found Ms Liu say no substantial trauma was evident. Ms Liu’s body was naked from the waist down, but investigators have seen no obvious signs of sexual assault.
A second cell phone found in the apartment was inactive and belonged to Ms Liu, Sgt Skubic said.
On Tuesday, Sgt Skubic sought to quell Canadian media reports Ms Liu had been stalked.
He said she had been asked out on dates and may have refused some, but none of the behaviour of her presumed suitors constituted criminal stalking.
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