OTTAWA, Ontario (AP) — A morning gas explosion in an Ottawa suburb Monday injured 12 people, including two children. Two men were seriously hurt and had to be pulled out of the rubble, officials say.

The blast destroyed four houses still under construction and damaged surrounding homes.

The two children were among six people taken to hospital immediately after the explosion, Ottawa Paramedic Services said. Two men had serious injuries, but all in hospital were in stable condition, paramedics said. Six injured people were treated and released at the scene.

Fire officials said the blast took place about 6:18 a.m. and that emergency responders used a chainsaw to cut through debris to rescue one of the men from the wreckage. About three hours later, they rescued a second person “surrounded by a large amount of debris.´´

Firefighters said a gas leak was responsible for the explosion.

Police were working with fire officials to investigate the blast, said Amy Bond of the Ottawa Police Service.

The homes were in a development built by Minto Group, which said it was providing temporary shelter in model homes for some of the people displaced in the blast.

Brent Strachan, the group’s president for Ontario, said the developer was cooperating with authorities in the investigation into the explosion, and that “our thoughts are with everyone affected.”

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