The West York Borough Police Department found the siblings, believed to be between 3 and 5 years old, walking in the street around Filbert and Adams streets at 9 a.m.
The boy was wearing a black tank top and shorts and the girl was in princess pajamas.
The children were unable to tell officers where they lived, who their parents are, or even their names, according to police.
The parents were located and the children were safely returned around 11 a.m.
It is unknown if the police are investigating this incident.
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