Detective Inspector Mark Loper, in charge of the investigation, said the inquiry was still in the early stages.
He could not provide a description of the attacker - and did not rule out the assault being gang-related.
Police were monitoring CCTV footage from surrounding businesses and working with neighbouring police stations to check through possible offenders known to police.
A number of parties going on at the time of the attack were also being investigated.
Mr Loper confirmed the attack was random and sexually motivated.
"We believe it is sexually motivated and that's because of the injuries.
"I don't believe [the attacker] would be out there again at the moment, especially in a small town if he's from here, with a lot of police here," Mr Loper said.
He appealed for information from anyone in the area at the time who may have seen the offender - either in the first instance or when he may have later returned "feeling remorseful".
"When you see this little 5-year-old who has come to New Zealand with her family at Christmas time and has just been viciously attacked it does affect the guys who are working on the case."
The girl's parents, who wish to remain anonymous, released a statement.
"For us, we want to get on with our daughter's recovery.
"Physically she is doing better and better. She started playing and drawing in her bed.
"We are very touched by the reactions of New Zealanders.
"This will still be a long journey for us and it will be made that much easier by the loving care and messages we've received from throughout New Zealand."
Bay of Plenty Police District Commander Glenn Dunbier, who met the girl's family hours after the attack, said it was too early to say how much longer the family would be in the country.
"They don't plan to do anything but getting their daughter well over the Christmas period," he said.
Neighbouring residents told the Weekend Herald of their disgust at the attack, and the community has begun a fund drive for the family.
Turangi and Districts Women's Club members Gill Greig and Beth Macgregor spent yesterday afternoon manning a collection bucket outside New World supermarket.
"It's just been an absolute shock to our whole community," Mrs Greig said. "We want them to know that New Zealand is a lovely country, and Turangi's a great little town."
One local, Bob Fussell, said news of the attack had "hit like a bomb".
"We are saddened something like this could happen in our presence."