GREELEY, Colo. (AP) — The mother of a 14-year-old boy allegedly kept locked in a filthy room in a mice-infested trailer for most of three years now faces a felony charge.

Weld County prosecutors Thursday charged Amanda Joliff with felony false imprisonment. Joliff also faces misdemeanor charges of child abuse and at-risk neglect. She originally faced only misdemeanor charges in the case.

Joliff, along with her boyfriend Richard Smith faced charges after the boy described by his mother as “developmentally delayed” was found hiding under a neighbor’s porch Sept. 27 in Erie, Colo.

Investigators found a lock on the plywood door to the boy’s room that Joliff told investigators she installed because he had once run away.

Joliff’s next court date is Nov. 17.

(Copyright 2011 by The Associated Press. All Rights Reserved.)