"If anyone recognises them please contact us - this crime is very concerning and we want to speak to this man as soon as possible.''
Anyone with a friend, flatmate or family member who returned home about 9pm last night barefoot with wet clothing was urged to contact police.
At a police press conference this afternoon, police said the girl's mother intervened when she heard her daughter's screams for help.
While playing with two friends, the girl was dragged by the man into a section of the reserve by a creek.
The girl's mother ran to her assistance when she heard screams.
Her attacker, who was wearing a black t-shirt, fled the scene, wet from the creek and leaving his "distinctive'' white jandals behind.
Mr Litherland said the girl was "traumatised'' and had been treated at hospital for scratches.
"This type of attack is not tolerated. It's traumatic for the young girl.
"We need to identify this individual. He could try this again.''
Police are appealing for information on the attack and say it is likely the man arrived home wet.
The man, believed to be a Henderson local, is described as young, skinny and of Pacific Island descent or mixed race.
"Because the offender ran through the reserve, he may have been at the intersection of Farquhar Road and Phelps Place shortly after, and we're hopeful that anyone who was in the area can think back to what they were doing last night and whether they saw someone of this description, between 8pm-9pm. This person has got home somehow wearing wet clothes and no shoes and someone will have seen him,'' Mr Litherland said.
There hadn't been any other similar attacks in the area, but having the man at large meant it could happen again, he said.
"It's very important we find him.''
The young girl is recovering from her ordeal with close family.
Anyone with information is asked to contact the Waitakere Police on 09 839 0627, or anonymously contact Crimestoppers on 0800 555 111.