Police say a man who assaulted a six-year-old girl outside a park in West Auckland was at the park the day before.
Detective Sergeant Peter Litherland told Radio New Zealand's Summer Report programme the suspect was spotted hanging around the playground for about 20 minutes on New Year's Eve.
The attack happened after the man approached a group of children playing outside the park on Wednesday evening.
When the children went to go home, he grabbed one girl and carried her inside the park. The girl's mother heard her daughter's screams and rushed into the park, scaring away the man.
Mr Litherland said the attack was sexually motivated and is concerned the man could strike again.
Police believe the man lives locally and is described as young and skinny. Mr Litherland said he would have returned home wet and without his white jandals, which were found at the scene.