Watch: Police say punch 'tactic' designed to subdue 13-year-old resisting arrest, after Auckland dad complains on Facebook

Police say an officer filmed punching a 13-year-old boy in the side during an arrest was "carrying out a tactic" to get him to release his arm.

The incident took place in the suburb of Pakuranga yesterday near the Pakuranga Highway, police confirmed, and the boy now faces charges of disorderly behaviour, failing to stop, dangerous driving and resisting police.

A video was posted on Facebook of the incident by Geoff Garnett, the father of the boy involved, who wrote "what is New Zealand coming to?"

"This is my 13-year-old son riding his bike in Highland Park, and look what the NZ police do to him," he wrote.

Mr Garnett said his son was only riding without a helmet, and refused to get off his bike and talk to police, which prompted them to give chase, the NZ Herald reported. 

However, area commander for Counties Manukau East Inspector Wendy Miller said there is another side to the story.

"Police had received a number of calls regarding the behaviour of a group of teenagers, with a member of the public telling police the boys were aggressive and trying to fight other people in the area," Inspector Miller said.

"Police staff quickly attended and tried to speak with the teenagers, however the main aggressor, who was 13-years-old, quickly tried to get away from police on a pushbike and was biking into traffic and ran through a red light.

"The officer managed to borrow another bike and followed him for several minutes and caught up to him.

"It is at this point that people were filming on their cell phones and you see police trying to handcuff the teenager who was resisting arrest.

"The officer is shown carrying out a tactic that can be used to get an offender to release their arm so that we can put handcuffs on them.

"Very often our officers are filmed on cell-phones and this is posted on social media ... more often than not these videos will only show a portion of what has happened and perhaps not surprisingly, rarely show the full circumstances, such as our staff being assaulted, abused or spat at."