The children's adoptive and foster parents, Mike and Sharen Gravelle, denied that they abused or neglected the children during a custody hearing on Monday in Huron County, Ohio.

No charges had been filed as of Monday night.

"The impression that we got was that they felt it was OK," said Lieutenant Randy Sommers of the sheriff's office in Huron County.

The Gravelles said a psychiatrist recommended they make the children sleep in the cages at night, County Prosecutor Russell Leffler said.

The cages were stacked in bedrooms on the second floor of their house, he said.

Conditions

The children, ages one to 14, were described as having conditions that included autism and foetal alcohol syndrome.

"The impression that we got was that they felt it was OK"

Sheriff's deputy Randy Sommers on the children's adoptive and foster parents, the Gravelles

They were found by a children's services investigator on Friday when he stopped by the Gravelles' home outside Wakeman, about 80km west of Cleveland.

Some of the cages were rigged with alarms, Sommers said; others had heavy furniture blocking their doors. The children did not have blankets or pillows.

One of the boys said he had slept in the cage for three years, Sommers said.

A neighbour recently reported seeing the children working long hours in the family's yard, he added.

The children were placed with four foster families on Monday.

Happy and loved

A woman who identified herself as Sharen Gravelle's mother but refused to give her name said the children were happy and loved.

"This year they have played and had fun and laughed like no other children have, which they have never been able to do"

Sharen Gravelle's mother

"This year they have played and had fun and laughed like no other children have, which they have never been able to do," she said.

Sommers said there were no apparent signs the children had been malnourished or beaten, but they were sent to a hospital for examination.

Their conditions were not available on Monday.

In March, a couple who had recently moved from Ohio to Florida was charged with neglect when their adopted teenager was discovered malnourished in a crib-like cage.

The then-17-year-old weighed 22kg, investigators said.