Investigators from the State Fire Marshall's office will spend this weekend trying to determine what sparked a massive apartment house fire in Augusta. While all the tenants got out, 7 were treated for minor injuries.

The fire caused the 18-unit building at 36 Northern Avenue in Augusta to collapse Friday. 27 people survived the fire, with seven taken to Maine General Hospital for minor burns, smoke inhalation, and hypothermia.

Public Safety spokesman Steve McCausland said in a press release on Friday that investigators will work through the weekend to try and determine what sparked the blaze. All they know, at this point, is that it started in the rear of the building on one of the upper floors. They plan to interview all the residents, who are now left homeless just before Christmas.

The good news, if there is any, is that the building had working smoke detectors and two exits out of each unit. This demonstrates, vividly, the role they play in surviving what could have been a deadly fire.