Fire investigators say a house fire may have been started deliberately in the early hours of Friday morning.
Fire crews from Halifax and Illingworth were called to the blaze on Brussels Court, Halifax, at 2am.
They delpoyed four firefighters with breathing apparatus to tackle the fire and had it under control in around 10 minutes.
However, the crews stayed until 5am making sure the property was safe for the residents to return to later today.
The two occupants had managed to get out of the building before the crews arrived but a Red Cross temporary home was called in to house them overnight.
The investigation may now be passed to the police for further inquiries.