Contra Costa County Fire officials say that an elderly woman and her adult son died in the fire, as one person was able to escape. They were treated on scene, but it is unclear what their condition is.
A small dog also died in the fire.
Fire crews responded to Countrywood Ct. where the fire started in a first-floor bedroom. Officials believe the fire was started by smoking materials, and that an oxygen machine helped spread the flames.
The fire spread to three units before it was extinguished.
Fire officials say that it was contained to three units and was extinguished. Officials have not identified the cause of the fire, which remains under investigation.
Stay with ABC7 News for updates on this developing story.