The alarm was raised shortly after midnight, and fire officers from four stations worked to put out the blaze, but it took 20 minutes for them to get there.
Eleven people were rescued from the house and were taken to hospital with minor injuries, but released soon afterwards. One person who was believed missing has been located.
The home was a care center for young people with psychiatric problems. The police tell Swedish Radio News it is possible arson was responsible, based on the way the fire spread so quickly. The technical investigation will have to wait, however, until the fire has been completed put out.
Swedish Radio News reports that Stockholm City Council had previously decided not to use the home, as it feared the level of staffing was too low to guarantee the safety of employees and residents.