Inside the apartment above one of the city's busiest streets, the officers found a woman dead. Their 33-year-old male suspect was loaded into an ambulance with a police bullet wound.
Vancouver Const. Brian Montague said a girl, about five or six years old, was taken to children's hospital with some injuries that aren't considered life threatening.
"Our officers attended and they were confronted by a man with a weapon. The officers gave him some commands and ended up firing their weapons," Montague told reporters outside the complex.
Montague said the call came into police mid-morning on Monday.
"The initial call did say there was yelling and crying going on. So it would be safe to say that the homicide, potentially, occurred around 10:30."
When officers entered the apartment the female victim was clearly deceased, he said. Police said they had not yet determined the relationship between the dead woman, the child and the suspect.
They did not release any names.
Yellow police tape blocked off access to the building on Kingsway in the city's eastside, keeping out residents and reporters.
Gurinder Sodhi, who owns the accounting firm below the complex and several units within the building, said he was alerted to trouble when someone told him about police vehicles and ambulances around the building.
He said the incident took place in suite 301, and he knew the residents in passing.
Sodhi said he saw paramedics load the man into an ambulance, bleeding profusely from his wounds. Police said the suspect was in stable condition in hospital.
He said he recognized the man from the apartment, where he lived with his mother. Sodhi said he had seen the woman with a child, who he assumed was her granddaughter.
While Vancouver police investigate the homicide, under provincial law any police-involved shooting is investigated by the Independent Investigations Office.
Robin Plomp, with the IIO, said the office was called minutes after the incident.
"The information was that the officers had response to a complaint of a child at risk, or a child welfare type of complaint. Upon arrival they had an interaction with a male subject who was shot."
Plomp said the man was armed with a knife.
He said two officers attended the call, but he's not sure if both of them fired their weapons.
The man who was shot is now under guard at Vancouver General Hospital, Plomp said.
While the IIO investigates the shooting, Vancouver homicide detectives will take over the investigation involving the death of the woman.