Police in Kitchener have confirmed that the deaths of a family of six, who were found in their home on Thursday, was the result of a murder-suicide.

Police also said they are treating the grandparents of the slain family in Kitchener as legal witnesses in the tragedy that wiped out an entire family on a quiet street.

The grandparents — Vilem and Mirka Luft — own the house on Mooregate Crescent where six members of the Luft family lived. The grandparents stayed in a recreational vehicle in the driveway.

Police confirmed the names of the six members of the family. They are Bill Luft, 42; Bohumila, his 27-year-old wife; and their children — Daniel, 7; Nicole, 5; Peter, 2; and David, 2 1/2 months.

Most of Friday, police refrained from saying, or speculating, on how the six family members were killed. They consistently maintained they are not looking for any suspects.

Records show Bill Luft was investigated three times within the past year by child protection workers. Two months ago, he checked himself into a hospital for psychiatric care.

Staff Sgt. Brent Thomlison said police are holding back from commenting until after the autopsies are completed.

"We have been treating the grandparents as witnesses to this tragedy," Thomlison said. "I know there's been a lot of conclusions drawn as to what occurred down there . . . whether it was a multiple homicide or a murder-suicide," Thomlison explained. "We won't speculate. Once we get confirmation of what occurred, we'll release that information, but before that happens, we won't."

The City of Kitchener has provided counselling sessions for residents to attend to cope with their grief. The sessions will be at the Victoria Hall Community Centre, down the street from the Luft home.

Thomlison has said there was "trauma" to the bodies. There have been newspaper reports that the wife was found stabbed to death in a downstairs room. Other reports say the father was found with the children, who had been shot.

Neighbours mourned the Luft family Friday, walking along the street, bringing toys and flowers as gifts and mementoes. Many wept openly as they walked along Mooregate Crescent.