KENT, Wash. -

The woman who triggered the May 5 Amber alert in Washington pleaded not guilty Tuesday to charges of kidnapping, burglary and custodial interference.

At her appearance in King County Superior Court in Kent, 34-year-old Sandra Bennatts was ordered to remain in jail with bail set at $1 million as her case continues.

Prosecutors say Bennatts, who lost custody of her 6-year-old son, took the boy from his grandmother's home in Auburn after attacking the woman -- her own mother -- and leaving her tied up.

The Amber alert was issued after the grandmother freed herself and called for help. Bennatts was arrested after a chase that ended when she ran out of gas on Highway 2 at Stevens Pass.