A huge fire has torn through a commercial building in Iraq's eastern city of Kut, killing dozens of people, local authorities said Thursday. About 50 people died in the overnight blaze, multiple Iraqi media outlets reported, citing the governor of the Wasit region. They identified the location as the Kut Hypermarket mall. Video footage shared on Facebook and geolocated by CNN showed a large multistorey building in Kut engulfed by flames, with a group of people gathered on the rooftop as firefighters battled the blaze. People were seen calmly filing out of the building, as flames raged directly overhead, in another video posted to X. Crowds gathered in a fenced area outside an unconfirmed location during daylight hours, with emergency vehicles parked nearby, photos posted on Telegram showed. The cause of the fire is not immediately known. Wasit's governor has declared three days of mourning for the victims of the fire, according to local media. CNN has been unable to independently verify the number of casualties from the incident. This is a developing story and will be updated. For more CNN news and newsletters create an account atCNN.com