Two people have been arrested after an autistic girl was found living in her own filth in a locked wooden cage in their home.

Both Mickey Sparks, 69, and Patricia Laws, 43, were charged with child abuse after the discovery was made by police on Monday during a welfare check.

Washington County Sheriff's department, Tennessee, confirmed officers had found "a locked wooden cage with a mattress and a child inside" during a search of a bedroom in the couple's house and that "the cage smelled of urine and faeces".

A statement from the Sheriff's office also said the 10-year-old girl, along with three other children who lived at the house, were all subsequently removed from the residence.

A court document cited by the Johnson City Press reportedly indicated Laws told deputies the state Department of Children's Services had approved the use of the cage as a way of controlling the girl but that police checks turned up no records of the alleged approval.