LONGVIEW, Wash. -- A woman accused of leaving her children to fend for themselves while she sold the family's food stamps for drug money made her first court appearance Thursday.

Investigators said Carrie Pena, the mother of 13-month-old twins and a 3-year-old girl, used methamphetamine in her bedroom while leaving her children alone in the apartment.

When officers found the children, they were wearing filthy diapers and their bodies were bleeding from diaper rash, according to Cowlitz County court documents.

The three children were found in an apartment where they were given little more to eat than crackers and water, investigators said in the documents. Authorities said all of the children had head lice and that they lay in urine-soaked beds covered with old food and garbage.

Investigators said Pena often relied on her 3-year-old daughter to watch over the twins and said Pena's pregnant roommate reported her to Child Protective Services.

Court records show Pena went to live in a Longview motel after finding out her roommate turned her in. The documents said she threatened to have the woman beaten.

Pena was arrested on charges of criminal mistreatment, intimidating a witness and endangerment with a controlled substance. She appeared in court Thursday.

According to court documents, the state terminated Pena's parental rights and the children are in state custody.

Tim Painter, a former neighbor, said he recalls Pena and that he can't fathom neglecting a child.

"My son is my world," Painter said. "I would never neglect my son."