Watch: CCTV video shows 'brutal, serious' assault as Auckland 20-year-old bashed unconscious with piece of wood - do you recognise attacker?

CCTV footage has been released showing a "brutal, serious" alleged assault in Auckland, where a man was knocked unconscious with a piece of wood. 

Police said in a statement the "violent, physical altercation" between the groups ended with a 20-year-old man receiving serious head injuries. 

He is undergoing facial reconstructive surgery. Another person was said to have his arms and legs hit with a piece of wood. 

It happened at 11pm on January 23 on Oates Rd, Glen Eden in Auckland.

Detective Sergeant Chris Goldsmith said it was a "particularly vicious and cowardly attack on a male who continues to be struck in the head with a plank of wood, despite lying unconscious on the ground". 

"We had to leave out the last part of the footage as it was too graphic to show, however the offender strikes the victim in the face while on the ground in what easily could have resulted in a fatal blow."

"We are determined to find these men and hold them to account over this shocking attack."

He said one man they are looking for is 1.82m tall of large build, and the other is 1.75m and of fit/muscular build. 

Anyone with information can call 09 839 0600 or anonymously on Crimestoppers on 0800 555 111.