Police believe a boy as young as 12 is behind a series of indecent assaults on women in south Auckland since last December.
The five attacks happened in the Papakura area on either a Sunday or a Monday and police believe the same male is involved.
He is described as a Maori or Pacific Islander, aged 12 - 16 years and of thin build.
On three occasions he has been on a bicycle.
"These brazen assaults are very distressing and frightening for the victims," Detective Colin Welsh said.
"We need to apprehend this offender as soon as possible to ensure he does not have the opportunity to do this to anyone else."
Similar incidents were also reported in Pukekohe and Papakura between December 2012 and March 2013.
Police said they feared there may be more victims and called on anyone who had had a similar experience in either of these areas to contact them immediately.
People walking alone, particularly in unfamiliar areas, were advised to avoid dark and isolated places, keep their cell phone in reach and if possible walk in view of traffic or other pedestrians.
"Dial 111 immediately if you see suspicious activity so that police can respond and prevent a crime before it occurs," Welsh said.