A girl who was with the group was in tears as she recounted how she hit the dog to try to get it off Stevie-Rebecca.
"I was scared she was going to die."
Her cousin said the dog jumped on Stevie-Rebecca and wouldn't let go. "It was pretty scary."
The dog was pulled off by a worker at Piako Tractors and emergency services were called.
Ambulance officers treated the girl before taking her to Rotorua Hospital with moderate injuries.
Some of the children ran to the injured girl's home to get her father, Gary Shipgood, after the attack.
An emotional Mr Shipgood said yesterday he was upset but also felt sorry for the dog's owners.
"They are going to have to put the dog down and I know this isn't easy."
He said his daughter was doing well after receiving stitches, including 20 to one wound, and had been released from hospital.
He did not want the dog's owners charged, saying they would be feeling bad enough already.
Rotorua District Council Animal Control supervisor Kevin Coutts said it was likely the dog owner would be charged, depending on what the victim's family wanted.
The dog owner said he was devastated, had apologised to the girl's family and wanted the animal put down.
"It's a big shock. It will be hard to put him down but it has to be done ... We are devastated for the family."
He had owned four American bulldogs in the past 12 years without any trouble and had thought Stevie-Rebecca, a friend of his daughter, may have been scared of Riley and that the dog had sensed that.
It was the third dog attack on a child in New Zealand in less than a week and the fifth in a month.