"They had sort of jumped out and grabbed us, I think they were just wanting a fight. I said to them, 'Here just take my bike, leave my friend alone', and they lashed out at me."
Nicholas' mother Susan Grey received a distraught call from her partner that afternoon to go straight to the hospital.
"I didn't know what I was going to find or expect especially since his dad was so emotional," Ms Grey said.
"Nick had just starting riding to school two weeks ago and you worry about traffic and trucks but you never think there's potential loss of life by some people doing this."
She said she had since been told that the scene of the attack was considered unsafe.
"I've lived here for 15 years and never knew it was a no-go area.
"I hope another mother reads this and will be aware in case their children also ride down there."
Karin Vincent said her son Jacob was with the two boys when he was stopped at the fence near the Utuhina bridge, pushed off his bike and punched in the face by a fourth boy.
"He said, 'mum, they were just laying into me'," she said.
Mrs Vincent said her son's attack ended with the help of a couple passing by and he was able to ride his bike home to Springfield to alert his mother, who also rang the police.
"Jacob said as he was riding up to the boys, he heard them say, 'Check, check, check it', before the attack. I can't believe this has happened in small-town Rotorua. Our boys are scared now, we live in a city where you can't even cycle home from school."
Spencer Hill, father of Callum, said his son had seen the group of boys near the bridge previously.
"Physically, he's fine. He's got a bit of a fat lip but psychologically - he's not going to get on his bike anytime soon," Mr Hill said.
"We'll be taking him to school and picking him up until he's ready and he absolutely won't be riding through that area again. Callum said those boys were hanging around that area for a bit now - I think it was a territory thing."
Rotorua police Inspector Stuart Nightingale said an arrest had been made in relation to the incident.
He said police understood the bikes had been recovered, thanks to help from the public.
"An active inquiry continues and we are confident it will lead us to the remaining suspects."
Mr Nightingale said the area of the attack was not known to be unsafe.
"Not particularly at all, people are mobile and any time they have a mindframe to take other people's property, we are keen to deter that and make people accountable for their actions."
-Anyone with any information is asked to call the Rotorua police station on (07) 349 9554.
