SE Calgary house explosion caused by natural gas buildup, investigators say

Calgary fire officials say a house explosion last week was caused, in part, by a buildup of natural gas.

Emergency crews were called to Mahogany Road SE around 3:15 p.m. Thursday after getting reports about an explosion and a large plume of black smoke coming from a townhouse complex.

Crews arrived to find a townhouse unit collapsed and destroyed with fire spreading to neighbouring homes.

In an update Tuesday, a Calgary Fire Department (CFD) spokesperson says a preliminary investigation suggests an end unit had a buildup of natural gas. The explosion happened when a furnace turned on in the home.

The explosion ruptured the natural gas line which led to the fire spreading to other units.

No one was inside the home where the explosions happened, but two people and two firefighters were taken to hospital with injuries.

Officials are still trying to figure out where the gas came from. The investigation is ongoing.