WEEHAWKEN - Prosecutors say an infant left on the steps of Weehawken High School has far more serious injuries than initially believed.

The 1-month-old girl was found Friday afternoon wearing only a diaper and wrapped in a blanket on the steps of the school. She was crying but appeared to only have a bump on her head.

But Hudson County Prosecutor Edward DeFazio tells The Jersey Journal the infant has multiple fractures, including a skull fracture, and is being treated at a Manhattan hospital.

Authorities believe the infant was only on the steps a few minutes. Her mother, a 37-year-old Weehawken resident whose name hasn't been disclosed, was found by police and has undergone a psychiatric evaluation.

She's been questioned but not charged.

Baby found on steps of Weehawken H.S. AP wire services contributed to this report.