Multiple fire crews have responded to a duplex fire on the 800 block of 6th Ave NE in Austin. Fire officials on scene tell ABC 6 News no one was home at the time and they have not made contact with the occupants of the two-story duplex. Flames and heavy smoke was seen in the air and firefighters were seen gearing up with oxygen tanks as they entered the home. Fire officials say it appears the fire originated in the attic. Crews say they expect to stay on the scene through the night. Austin police, fire and rescue along with Mayo Clinic Ambulance are also on the scene.