This undated photo provided by Fredericton Police Force shows Const. Robb Costello. But the 75-year-old woman said she couldn't flee to safety while her pet remained in potential danger. The two other victims have only been identified by police as an adult man and woman.
A suspect is in custody as police continue to investigate the incident, but no names are being released at this time.
That CBC report adds that there has been massive emergency services response to the area, including police, paramedics and firefighters.
"The police were here earlier and wanted me to leave, but I said I couldn't leave my dog behind".
Several other victims were being treated at a regional hospital, but there were no immediate details on the nature of their injuries or their conditions.
The small city lies on a curve of the St John River in eastern Canada.
It was something his common-law partner, Jackie McLean, tried to remember on Friday after learning he was one of four people shot dead in a quiet residential neighbourhood in Fredericton.More news: Kerala floods: Eight columns of Army deployed for rescue operations
One block down the road from 200 block area is a small strip-mall with a Subway and a Tim Hortons. She heard the gunshots from the apartment down the street.
"We'll see where this investigation leads in terms of what exactly happened, who did it, what was the motivation for doing it and the instruments of destruction that were used", he said.
"My adrenalin was going like a bat out of hell". "I'm on my floor", he said.
With her building under lockdown, she headed to her bedroom for a couple of hours, until it was over.
He called 911, heard more shots and took another glance out the window.
Our hearts are broken by the murder of our two fearless police officers. "During this hard time, our thoughts are also with the courageous women and men on the front lines working to keep us safe", Gallant said.
Forget immediately called the news into her dispatch. While staff said they kept the doors locked, the kids carried on with normal life, playing with toys or watching a movie as the police investigation unfolded. "Doors are locked and everybody's inside".More news: Rookie RB Guice has sprained MCL
"I'm still timid about going out", she said at 3 p.m. "I'm anxious for the other people around me".
"I'll be staying here".
A resident said he heard a series of "firecracker" sounds around 7 a.m. local time, according to the CBC.
"It sounded like the first one came from right outside my bedroom window", MacCoubrey said. "I am hoping that we will be able to put something like that together".
"Then two more happened within the first three minutes".
Speaking to Global News, another resident, Dave MacCoubrey, said that he could have heard as many as 17 shots coming about 30 feet from his bed. "In this time of shock and grief, let us all protect their families", Fredericton's mayor, Mike O'Brien, said on Twitter.
Outside the scene, New Brunswick Premier Brian Gallant urged the public to be patient in waiting for answers. "During this hard time, our thoughts are also with the courageous women and men on the front lines working to keep us safe", he said.More news: Chinese state media labels Trump's trade policies 'extortion'