Children playing with a lighter started a fast-moving blaze that ripped through an apartment complex attic, destroying one unit, damaging several others and displacing about 55 people, Santa Rosa fire officials said Friday.

The two elementary school-aged children were on a couch on a patio near the front door of an end unit when the fire started about 2:15 p.m. Thursday at the single-story apartments on Aston Avenue, Assistant Fire Marshal Paul Lowenthal said.

Flames quickly engulfed the couch and set fire to the building. Parents and other siblings who were inside got out and no one, including the two children with the lighter, was hurt, Lowenthal said.

Fire and smoke filled the end unit and spread through an open attic above another three units, putting firefighters on a mission to stop the blaze as it smoldered through a cellulose-based insulation material and threatened an additional six units, Lowenthal said.

Of about 55 residents of the apartment complex, no one could return home because of the damage or because utilities were cut during the firefight and cleanup. The Red Cross housed about 25 people Thursday night at a shelter at the First Presbyterian Church on Pacific Avenue.

Lowenthal said all but about 17 people will be able to return home Friday evening once power is restored to the undamaged units, estimated to take place by about 5 p.m.

You can reach Staff Writer Julie Johnson at 707-521-5220 or julie.johnson@pressdemocrat.com. On Twitter @jjpressdem.