PALMDALE, Calif.—Los Angeles County sheriff's officials say the adoptive mother of two children is in custody after they complained of being tied up and beaten.

County prosecutors say Ingrid Brewer pleaded not guilty Wednesday to eight felony charges, including torture and cruelty to a child.

Sgt. Brian Hudson says deputies responded to Brewer's Jan. 15 call saying the 8-year-old boy and 7-year-old girl were missing.

The children were found hiding under a blanket, lying on the ground nearby. Neither had winter coats on, despite frigid temperatures.

The children allege they were locked into separate bedrooms when Brewer went to work each day and forced to use wastebaskets for toilets.

Hudson says marks and injuries on their bodies were consistent with the abuse they described.

Brewer is due in court Jan. 31.