As part of his attempt to justify his actions, Harris has claimed the young girls, and their eight-year-old sister whom he also took in but did not formally adopt, were threatening to kill his family.
Harris, who has three biological sons, said the eldest girl, who was eight, said she would 'kill everyone in the family'.
He took the death threat so seriously, he said, that he, his wife and their three sons barricaded themselves in a separate room at night for safety.
Harris also claimed that another of the girls 'crushed a family pet to death', further convincing them to get rid of their recently-adopted charges.
He did not specify what kind of pet it was, nor whether the three-year-old or the six-year-old was responsible.