Video of "one-punch" assaults that happened within minutes of each other in Auckland have been released.

Three people were knocked out from single punches on July 2. Police are seeking information on the "cowardly" attackers in the footage.

The first attack occurred at 4am on Jean Batten Place. The victim was punched once and knocked unconscious. He suffered a fractured nose, stitches to the head and bruises to his elbow, tailbone as well as cuts to his upper and lower lips.

The next attack happened only five minutes later and just around the corner on Fort St. The offender punched two people rendering both victims unconscious. The first victim suffered a concussion and a displaced jaw, while the second victim also suffered a concussion and a wound to his face.

Auckland City Police are seeking a man once ' coward punc ' attack was caught on camera in Auckland's CBD

Police say the incidents are not related, but both are being investigated.

Detective Inspector Chris Cahill said it was incredibly alarming to see such violent behaviour, which can have life-altering consequences for victims.

"The unprovoked attacks in these videos are appalling and we are appealing to members of the public who know who these offenders are to get in touch with the police immediately."

The first video shows the offender in a black jacket, dark hat and white pants. In the second video the offender appears to be strongly built and wearing a white T-shirt, dark pants and white shoes.

Police urge any members of the public who may know who these offenders are, or have witnessed these events to contact Constable Luke Curran on 021 191 2672 or contact Crimestoppers anonymously on 0800 555 111.