A massive explosion that levelled a Mississauga home and damaged dozens of others was deliberately triggered as part of a double suicide, police say.

The explosion, which occurred at a residence on Hickory Drive on June 28, killed 55-year-old Diane Page and her husband, 55-year-old Robert Nadler.

At a news conference held on Friday afternoon, police said that they have determined that Page and Nadler intentionally disconnected two natural gas pipes leading to a basement hot water tank in order to bring about the explosion.

Police also said that they are confident that the explosion was a double suicide and not the result of a double murder or murder-suicide. The cause of death of both Page and Nadler was blunt-force trauma consistent with having been near the epicenter of the blast, police said.

“We had a witness indicate that they were able to smell the gas an hour-and-a-half prior to the explosion, so these two individuals would have had ample opportunity to exit the residence,” Peel police Const. Raj Klair said on Friday.

Notes found at scene

The daytime explosion sent debris flying hundreds of metres from the blast zone and prompted authorities to issue an evacuation order that initially affected 700 residences.

Klair said that police have ruled the blast a double suicide based in part on the ample time that Page and Nadler would have had to escape as well as the content of some handwritten notes found amid the debris.

Those notes, which police believe were written by Page, were “consistent with someone suffering from some sort of depression,” according to Klair.

“The notes were part of it, the messages in those notes,” the constable said.

Several questions remain

Though officials now consider the case closed, several questions will remain unanswered.

Police said that a pathologist was unable to determine where in the home Page and Nadler were located at the time of the blast, though it was determined that they were alive.

Mississauga Fire Chief Tim Beckett also said it is impossible to determine what actually ignited the natural gas that had built up inside the residence.

“Once the natural gas enters its explosive range any ignition source ranging from electric circuits to an occupant using an open flame could have ignited the natural gas and caused the explosion,” he said.

33 homes remain empty

A total of four homes have been demolished due to damage from the explosion and as of this week 33 families remain displaced.

Mississauga Mayor Bonnie Crombie said that “a lot of issues remain,” particularly for residents still waiting on insurance settlements.

“It is a tragedy for everyone involved,” she said, noting that the city will hold a meeting for displaced residents next week. “We feel for those 33 families that are still out of their homes and we are working with them to ensure they can get back."

As part of their investigation, police interviewed more than 65 people.