Police are appealing for information after a baby was seriously injured in Porirua's Titahi Bay late last year.
The three-month-old boy was admitted to Kenepuru Hospital on New Year's Eve before being transferred to Wellington Hospital, where specialists determined he had non-accidental fractures to nine separate parts of his body, police said.
The hospital notified police and inquiries into the circumstances of the baby's injuries began on New Year's Day.
Detective Senior Sergeant Rebecca Cotton of the Wellington Child Protection Team said the incident "is incredibly traumatic for all involved", urging anyone with information on the "serious assaults" to come forward.
"If anyone in Titahi Bay, or the wider community, has seen or heard anything that may assist our enquiries, please get in touch."
Anyone with information is asked to call 105.
The baby — now six months old — is currently in the care of extended family, police added.