A police officer who was seriously assaulted by a group of men in Kawhia last night used pepper spray and a taser to try and subdue his attackers.

The policeman had been set upon by at least five people, who were kicking him as he coiled up in pain on the Kawhia wharf.

The group took his taser, his radio and his pistol and were only stopped when local firefighters and the public stepped in to intervene.

Although the officer had called for back-up, his closest colleagues were 70km away in Ngahinapouri and couldn't make it to the scene in time to put a quick stop to the attack, which left him with serious bruising and grazing to his face, arms and body.

Police have painted a detailed picture of the events leading up to the attack and are appealing to the Kawhia community to help identify who was responsible.

Three people, including a father and son, appeared in court today facing charges of aggravated assault and assault with intent to injure, but at least two more offenders remain at large.

The policeman, who is now at home recovering with his family, had located a 19-year-old man with outstanding arrest warrants shortly before 6pm last night.

A stand-off between the two men ensued and a relative of the 19-year-old was subsequently called to help de-escalate the situation, but he ended up setting on the policeman instead.

The policeman used pepper spray on the offenders, which had little effect, and then presented his taser, which was grabbed by one of them.

The officer was able to break free and use his taser on the main offender, who had rushed at him, police said.

He was handcuffing the man when he was struck from behind and knocked to the ground.

"From there the officer has been kicked on the ground by a group of what we estimate to be five people and he has crawled into a ball and activated his Officer Safety Alarm," inspector Rob Lindsay said.

"Cambridge staff at that time were at Ngahinapouri and were dispatched to go to the officer's assistance."

Aware of the situation and the policeman's isolation, his colleagues called the local fire brigade, who arrived at the wharf to find the officer on the ground being attacked.

The policeman's taser, pistol and radio were all taken from him.

"Fortunately for all concerned a member of the public recovered the officer's pistol and took it to the firefighters who secured the weapon," Lindsay said.

"A short time later police reinforcements arrived from across the district and the 19-year-old man, his 49-year-old father and a 21-year-old male associate were arrested without further incident."

The injured policeman was examined by ambulance staff and a local doctor and was to undergo further assessments today.

"The officer has asked me to acknowledge on his behalf the bravery shown by the firefighters and members of the public who's direct action prevented what could have been a far more serious outcome," Lindsay said. "It is these people who are the true spirit of the Kawhia community."

It was the fifth attack on Waikato police over the holiday period.

"Here we have a uniformed member of a small community trying to protect that same community," Lindsay said.

"With this being the fifth attack on officers as they try and assist people in need the message needs to be clear that such attacks on our staff will not be tolerated."

Anyone with information is asked to contact police on 07 858 6200 or call Crimestoppers anonymously on 0800 555111.