The force released more details about the city's latest homicide — its third so far this year — which was discovered mid-morning on Monday when officers responded to a 911 call from someone who reported hearing a child crying, a man yelling, and an apartment building hallway stained with blood.
When the officers arrived, they were confronted by a man holding a knife, police have said, and a short time later the man was shot.
The woman, 63-year-old Yin Nor Hsao, was pronounced dead at the scene, while her 19-month-old granddaughter was taken to hospital.
Crown prosecutors approved charges Tuesday of second-degree murder and attempted murder against Ka Chi David Siu, 33, who police said is the Hsao's son and the uncle of the injured girl.
Const. Brian Montague said the grandmother was babysitting her granddaughter, as she often did, while the child's parents were at work.
Montague said the girl was in hospital with "significant injuries."
"(The girl) is expected to survive, but the extent of her potentially life-altering injuries are not really known at this time," he said.
Montague said Sui was in hospital in stable condition under police guard, where he was expected to stay until he is well enough to be moved to jail.
Siu has no criminal record and only limited contact with police, said Montague.
"Mental health is probably going to be a factor here — that's something our investigators will look at," said Montague, who did not specify the nature of the mental-health issues.
Montague said police were last called to the apartment six years ago. He didn't say what the call was about, but he said it wasn't criminal.
The province's Independent Investigations Office, which handles serious cases involving police, is looking into the circumstances of the shooting.
The agency said it did not have any new information to provide on Tuesday.
The office has previously said two officers were at the scene, though it wasn't clear whether both fired their guns.
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