Firefighters responded to a blaze around dawn last morning in Crosby, 20 miles (32 kilometers) northeast of Houston. Authorities are trying to determine what sparked the fire.
Harris County Fire Marshal's Office spokeswoman Rachel Moreno says investigators believe all three people lived at the complex.
Sheriff's Deputy Thomas Gilliland previously had said two women and a boy were unaccounted for following the blaze. Gilliland later said it appears the victims succumbed to the fire. Autopsies were ordered. Names and further details on the victims weren't immediately released.