South Boston fire ruled a double homicide

Boston Police have released a statement on the fire that killed Acia and Sophia Johnson on April 6:

The [Office of the Chief Medical Examiner] has determined that the manner of death is homicide, caused by smoke inhalation and thermal injuries. The victims, both identified as a result of dental comparisons, have been officially identified as 14 year old Acia Johnson and 2 year old Sophia Johnson, both of South Boston.

Earlier:
Two kids die in South Boston fire that might have been set