The Office of the Fire Marshal is investigating a deadly explosion that police say “obliterated” a home in Caledon and displaced dozens of residents on Sunday morning.

At around 6:20 a.m., emergency crews were called to a house on Maple Grove Road for a reported house fire.

Firefighters arrived to find 9 Maple Grove Road completely levelled by an explosion and a large amount of free-flowing gas.

One person was located at the scene without vital signs and was later pronounced dead. OPP have since identified him as 54-year-old Joseph Westcott.

“We have gas shut off to the immediate area so the scene is somewhat stabilized for us. We have a primary search still (underway) to search the debris field,” Caledon Fire Chief Darryl Bailey told reporters on Sunday afternoon. “At this time, we have no information to believe that there was anybody else in the residence.”

Approximately 10 to 15 nearby homes have been evacuated, displacing between 30 and 35 people, Bailey said.

“We are not anticipating having to increase our evacuation zone,” he added.

Officials don't know when residents can return

A timeline has not been provided to residents on when they can return home but Bailey said the structural integrity of many of the houses will need to be assessed by the building department.

“There are houses to the right and left, as well as across the street, that are covered in debris. Windows have been smashed, garage doors have actually been blown up,” OPP Const. Ian Michel told CP24 on Sunday morning.

“There have been vehicles that have been damaged as a result of the explosion, bricks and wood as well. There is a wide damage area around the residence.”

Vince Griffo, who lives near the site of the blast, said he and his wife woke up to a loud bang and thought a tree had fallen.

"I ran down and I noticed that my back door was wide open. My sliding door went through my kitchen table. I still thought someone had broken in at the time. My wife went to the front and all of the neighbours were outside," Griffo said.

"We found out afterwards that the house actually blew up."

Another woman who spoke to CP24 said she first thought the explosion was an earthquake.

"I had both of my dogs in my room and one jumped on the bed because he was so startled and we have been awake ever since," she said.

Caledon Mayor Allan Thompson said the town is working to make sure those displaced by the explosion have all of the support they need.

“We are going to work with the families so the kids can get their homework, get their stuff,” he told members of the media on Sunday. “We are making sure that everybody has got their medication. We are making all of the pets have been accounted for. These are the next steps for the community.”

He said Mississauga’s response to a massive, deadly house explosion in 2016 has taught the Town of Caledon valuable lessons about how to respond.

“Our emergency work plan has worked extremely well,” he said. “One thing that has made it move so efficient is what the community has done… Everybody is asking, ‘What can we do to help.’”

He added that many people have offered to open their homes to those who have been displaced.

Cause of the blast still under investigation

The cause of the explosion has not yet been determined but the Office of the Fire Marshal's investigation is underway.

“At this point it is too early to speculate,” Bailey said.

Members of the OPP’s search and rescue team, as well as the Chemical, Biological, Radiological, Nuclear, and Explosives unit, were also on scene on Sunday.

OPP Insp. Ryan Carothers asked members of the public to avoid the area if possible.

“This is going to be an active investigation, an active scene I’m going to hypothesize for at least a couple of days,” he said.