The friend pulled the dog off twice before an adult female at the house stepped in and managed to get the dog away. The dog was then locked in a shed and an ambulance called for.
The boy was treated in an ambulance outside the house before being taken to Whangarei Hospital for treatment for the wounds to his face, arms and legs and then released.
Police Sergeant John Larkin said the dog belonged to a person who lived up the road but the dog had only been at the new address since last Wednesday. Larkin said police were told the dog was used to being around children.
The owner arrived at the house and surrendered the dog to animal control officers. The dog was destroyed yesterday.
There were about 122 infringement notices issued to dog owners in Whangarei last year, including 10 for serious attacks - mostly on other animals - that resulted in bite marks and puncture wounds.
Environmental Northland figures show only one dog owner has been prosecuted in court.
Whangarei man Paul Logan last month pleaded guilty to three counts under the Dog Control Act after his dogs attacked a mental health worker, causing serious injuries.
In December last year there were 9874 registered dogs in Whangarei.
Environment Northland manager Keith Thompson said there were 116 infringement notices issued in 2012, when there were about 13 serious attacks.
Of the 10 serious attacks in 2013, about 75 per cent were against other dogs, and all of the attacking dogs had been put down.
In two cases, pet dogs had been killed, while others required stitches or treatment for bites and punctures.
Mr Thompson said although a disproportionately large number of pit bull and pit bull-cross dogs had been involved in attacks, a survey carried out a few years ago found that labradors were most likely to bite.
