Calgary police have charged a man in connection with the deaths of his two children, whose bodies were found in a home in the northwest part of the city.

When police entered the home on Friday night after receiving a frantic 911 call, they found the bodies of a 13-year-old boy and a nine-year-old girl.

Police said it appears a woman, reported to be the children's mother, was the first to stumble on the scene.

"The preliminary information indicates that she had arrived home and that's where the first contact was made with the police," Insp. Guy Slater of the Calgary Police Major Crimes Unit said at a Saturday news conference.

Calgary Police Chief Rick Hanson told reporters Saturday that after officers discovered the bodies, they continued searching the home and found a man and a woman involved in a struggle upstairs. 

Hanson lauded the officers for their quick action, which he said may have prevented another tragic outcome. "It is our firm belief that the rapid intervention of our officers interrupted a potential homicide," said Hanson.

The woman was taken to hospital where she was treated for minor injuries. Officers arrested the man.

James Bing Jun Louie, 43, is facing two counts of second-degree murder and one count of attempted murder.

The incident has shocked members of a community popular with young families.

Neighbours told CTV Calgary that up to three children, including two teenagers, live at the address. All of those who spoke with CTV mentioned the family was quiet and kept to themselves.

One neighbour who did not want to be identified said she would sometimes see the children playing soccer outside, and she would hear the sounds of them playing the piano.

"We used to hear them. We don't see them much, they're a pretty quiet family," she told CTV Calgary.

James Bing Louie is expected to appear in court Monday morning.

With a report from CTV Calgary