CHICAGO (CBS) — Cook County Sheriff’s police said they are continuing to investigate how a 3-year-old girl ended up alone near a forest preserve in northwest suburban Prospect Heights on Tuesday.

The girl, whose name is Aliya, was found around 6:30 p.m. walking along Palatine Road, on the western edge of the Allison Woods Forest Preserve.

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“She had been brought to the forest preserve by, we believe, by a family member, and then found wandering along the street,” said Cara Smith, with the Cook County Sheriff’s Office.

Smith said Aliya only knew her first name, and not her parents’ names, and she had been wandering around, crying, before three good Samaritans spotted her, and stopped to help.

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“We were able to identify her, and make sure that she was safe, but she was found wandering along Milwaukee Avenue, south of Palatine Road,” Smith said.

Aliya’s father was in custody Wednesday afternoon. Police said the father has apparent mental issues.

The girl, who is from Lake County, was placed in the custody of other relatives, while a criminal investigation is underway.

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The Illinois Department of Children and Family Services also was investigating.