Mr Carpenter said as one officer tried to calm the crowd the second officer got the offender under control and placed him in the back of the patrol car.
"About this time a large male has run at one of the officers and king hit him from behind, knocking the officer to the ground as the crowd surrounded the patrol car.
"The uninjured officer activated his Officer Safety Alarm while his dazed colleague managed to get into the patrol car.
The officers then retreated from the advancing mob and reinforcements were dispatched, Mr Carpenter said.
Both parties were shut down as officers from Hamilton and a dog team arrived.
The injured officer was then taken to a medical centre and treated for grazing and a cut above one eye.
Mr Carpenter said police would not tolerate such attacks and those caught assaulting police officers would face the full brunt of the law.
"This type of behaviour is not only cowardly, it is totally unacceptable.
"Here we have two police officers working Christmas Day helping to keep the public safe, responding to a 111 call from the public, who are then set upon by a large intoxicated mob.''
Mr Carpenter said police believe they know the identity of the constable's attacker and further arrests are likely.
Five in court after taser turned on police
In a separate incident, five people have appeared in court in connection with the attack on two Northland police officers in which one officer was knocked unconscious and nearly tasered.
The two officers were hospitalised after the attack by a group of youths in Dargaville. One had fired his taser twice in a bid to fend off his attackers. Pepper spray was also used to subdue the mob.
One woman allegedly used a brick as a weapon and tried to shoot an officer with his own taser after it was taken from him.
When she was unable to fire it, she smashed it.
In the Christmas Day attack, the two policemen were punched to the ground then kicked after responding to a call from church-goers who saw teenagers damaging letterboxes and streetsigns about 8pm yesterday.
Police had followed the youths to a house on Tirarau Street where a party was underway.
Party-goers became aggressive and the officers were assaulted.
One officer was knocked unconscious and as the second officer attempted to protect him, he was kicked in the head and suffered facial bruising.
Police were assisted by the local fire brigade.
Seven people were arrested - five men and two women - on charges ranging from intentional damage, assault on police and escaping custody. Five of the accused, aged between 17 and 28, appeared in Whangarei District Court this morning. Three were remanded in custody. A 16-year-old boy charged with wilful damage is expected to be referred to police youth aid.
Police say more arrests are likely.
Both injured officers were taken to Dargaville Hospital, placed under observation and treated for their injuries. They were released shortly after midnight.
Whangarei/Kaipara police area commander Inspector Tracy Phillips said police were still piecing details of the incident together.
"We've still got all of the witnesses to interview - including the two police officers who weren't in a state to be interviewed last night.''
Ms Phillips said the incident was first attended to by a solo officer who then called for backup when the situation escalated.
"Dargaville is only a small place. Back up arrived fairly quickly and then further back up was required.''
Ms Phillips said the original incident was "low-key'' which didn't require a team policing unit.
"I'd have no issue with a police officer attending an issue like that by themselves - certainly I would have felt quite comfortable being by myself - but, you never know quite what you're going to or how it's going to evolve.''
The officer had been "painting'' people with the taser - unholstering the weapon and demonstrating he was prepared to use it - before it was taken off him, she said.
"It's used as a sort of prevention tool as well and he had actually fired the taser twice.
"When he was rendered unconscious of course it's difficult to keep hold of things like that.''
Pepper spray was also used in an attempt to subdue the crowd, Ms Phillips said.
"Had the people been rational and sober I doubt that this would have happened, quite frankly.''
Police are appealing for witnesses to contact Dargaville police.
The attacks came only days after police commissioner Peter Marshall appealed for people to take responsibility for their families and friends over Christmas.
Last weekend a male police officer was seriously assaulted and repeatedly punched in the head after being called to a dispute over Christmas lights.
In a separate incident, a relatively new female officer had her ankle broken while attending a family violence incident.
The break was so severe she required surgery. Both those attacks happened in the Waikato.
Mr Marshall said drunken violence against police would not be tolerated.
"It is simply not ok that staff attending such a minor and easily resolvable issue are subject to a serious assault.''
