OTTAWA, Ontario (AP) — A blast caused by a gas leak early Monday seriously injured two people and destroyed several homes under construction in a suburb of Canada’s capital, officials said.

Emergency responders pulled two people from the wreckage in the Ottawa suburb of Orleans and brought them to a hospital where they were in serious but stable condition, Reid Purdy of the Ottawa Paramedic Service said.

Three additional people were taken to hospital with minor injuries. Another five people were assessed at the scene and released. It was not immediately clear if the victims were residents or construction workers.

The explosion occurred about 6:18 a.m. local time and affected four homes under construction, Ottawa deputy fire chief David Matschke said. The Ottawa fire service said earlier that the explosion was caused by a gas leak.

Police were working with the Ontario Fire Marshal’s office to investigate the blast, Amy Bond of the Ottawa Police Service said.

Orleans South city councilor Catherine Kitts called the explosion “an incredibly distressing event″ for residents.