A New Zealand woman has been arrested on a child neglect charge after a bus driver found a two-year-old girl alive in a suitcase that was stowed in the luggage compartment.

The bus driver noticed movement inside the bag during a planned stop on Sunday at the settlement of Kaiwaka, north of Auckland, after a passenger asked for access to the luggage compartment, Detective Inspector Simon Harrison said in a statement.

The driver opened the suitcase and discovered the two-year-old girl, who was very hot but otherwise appeared physically unharmed, Harrison said.

The child was taken to a hospital, where she remained on Sunday night.

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The arrested woman was charged with ill-treatment or neglect of a child and will appear in court on Monday.