Updated 2/17/2012 at 10 p.m.

CHICAGO (CBS) – An 8-year-old boy Palatine boy who was the subject of an Amber Alert Friday has been located — alive and well, police say.

Illinois state police say Eriberto Perez was found unharmed in a traffic stop at 9:45 p.m. Friday near downtown Chicago. He had been taken by his mother’s boyfriend, 30-year-old William Cruz, Thursday evening.

The child’s mother, Erika Rivera, said Cruz told her he was taking Eriberto to pick up some doughnuts for the family. But later in the evening, Cruz told her in a cell phone call that the two were instead driving to a relative’s house in Chicago.

Rivera says her son sounded frightened over the phone.

“He sounded like scared, like (Cruz) told him, ‘Don’t say nothing,” she told CBS 2’s Suzanne Le Mignot.

Eriberto is Rivera’s oldest child. His father is deceased.

She said she had recently told Cruz she planned to leave him.

State police say Eriberto, once found, was taken to the hospital as a precaution. Cruz was taken into custody.

suspect1 Missing 8 Year Old Palatine Boy Found

William Cruz, 30, is sought in the disappearance of an 8-year-old Palatine boy. (Palatine Police Department)

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