"As this is ongoing, we are unable to comment further at this time," she said.
Baldwin went fishing with his family at Stillwater near Whangaparaoa on Sunday afternoon when he was attacked.
After arriving at the beach, Baldwin and his two siblings asked their mother if they could pat a dog.
Mother, Angela Rowley, told her children to avoid the dog, but she said the dog's owner insisted it was friendly and encouraged the children to pat it.
"The owner of the dog said, 'She is fine, she loves kids, she has grown up with children all her life', so they went and patted her," Rowley said.
Looking away for one moment, she heard the dog growl and then a child scream.
"I turned around after hearing a growl to see my son holding his face screaming."
She said she did not know the breed of the dog but described it as brindle.
The owner of the dog quickly left the scene after the attack without giving any contact details, Rowley said.
She and her son gave statements to animal control officers who came the beach to investigate.
"They will keep an eye out and will do some door knocking up a street the owner said he lived on to a local," Rowley said.
Rowley said her son hadn't wanted anyone to see him with the facial stitches. Doctors had predicted it could take up to six months to come right.