The local fire department received reports of a fire on the fourth floor of a building in the Kita district at 10:18 a.m local time. The fire was almost extinguished by 10:46 a.m., according to the department.
Video from NHK showed firefighters battling the blaze as smoke billowed out of the windows.
There are still no details on what may have started the fire, according to public broadcaster NHK.
A total of 28 people were injured, including the 27 feared dead, according to an officer at Osaka Fire Department.
This is a developing story, more to come.