Ottawa police say four children and two adults are dead and a seventh person is injured after what the police chief is describing as an attack by a “lone actor” in an Ottawa suburb Wednesday night.

Police chief Eric Stubbs told CBC News in an interview that it was a “mass shooting,” but an Ottawa police spokeswoman is not confirming the weapon.

Police were called to a townhome in Barrhaven shortly before 11 p.m. Wednesday and discovered the bodies in what Stubbs is calling “a horrific scene.”

One man was arrested very shortly after police arrived, and Stubbs says there is no ongoing threat to public safety.

He says police are still trying to determine the relationship between the suspect and the victims but it did not appear to be a case of domestic violence.

A seventh person was taken to hospital with serious but not life-threatening injuries.

None of the victims have been identified.

“A mass shooting like this, with this amount of victims, is not a common occurrence in this community,” Stubbs told CBC. “It is a safe community.”

Barrhaven is a fast-growing suburb about 20 kilometres south of the city’s downtown core. The townhouse is located on Berrigan Drive, a busy through street located within a block of two different elementary schools.

On Thursday morning, five marked police cars were parked on the street and in driveways near the home, which is a middle unit in a row of brick townhouses. 

A neighbour several doors down from the home who did not want to give her name said she heard a lot of yelling at around 10:30 p.m. Wednesday and that by 11 p.m., at least a dozen police cars were surrounding the home.

Several investigators in white jumpsuits were going in and out of the home throughout the early morning on Thursday. 

At around 9 a.m., investigators began loading something into a van parked in the driveway, while other officers blocked the view of the front door with a white sheet.

A stretcher sat behind the van.

Neighbours, many of them walking their kids to school, were horrified by the scene unfolding before them.

Ahmed Saed was walking his son to the school about a block away from the home Thursday. He said he lives nearby and walks his son past the home every morning.

“This is unbelievable for the whole neighbourhood,” said Saed.

Stubbs said police were still confirming the identities of all the victims. 

Sharlene Hunter, a spokesperson for the Ottawa Catholic School Board, said she had not been told if the children attended one of the board’s schools but said students and staff will be provided with any assistance or support they need.

“We at the Ottawa Catholic School Board want to express our deep sorrow for the tragic events that occurred in the Barrhaven community,” she said. 

“Our thoughts and prayers are with all affected by this loss.”

Katie McNelly, who lives a short drive away, said she considered keeping her kids home until the police made clear there was no ongoing threat. She said she is in disbelief that it happened.

“What could cause someone or people to do this, you know, annihilate six people that had their lives to lead,” she said. “I’ll definitely be hugging my family a bit tight tonight.”

Police said investigative teams remain at the site and asked anyone with information to contact the homicide unit.

Ottawa Mayor Mark Sutcliffe called the news distressing for all of the city’s residents.

“I was devastated to learn of the multiple homicide in Barrhaven, one of the most shocking incidents of violence in our city’s history,” Sutcliffe said in a post on X.

Ontario Premier Doug Ford also offered his condolences.

“This morning’s news is heartbreaking,” he said on X. “My thoughts are with the family and friends of the six victims and the entire Ottawa community who is reeling from this terrible tragedy.”

Police said a media update would be provided later Thursday.