Hamilton Police investigating a machete attack on a man in the city last month are hoping the public can help identify a mystery witness.

Detective Tom Evans of the Hamilton CIB said a 25-year-old man required surgery at Waikato Hospital after suffering serious leg injuries in an attack in Hamilton East on October 12.

 "The victim recalls very little about what happened other than he had gone into Hamilton's CBD on the Thursday night and met up with a group of males.," Mr Evans said.

"Our victim recalls going back to a Francis St address with one of the male occupants of the address and a third man known only as 'Joe'."

At some stage during the evening the victim suffered serious leg injuries with a weapon, understood to be a machete.

Mr Evan said the injuries to the man's legs were serious enough to require surgery while he also suffered injuries to his right arm.

"One of the challenges faced by the enquiry team is that we are yet to identify all witnesses to the attack and we are hoping someone out there may recall a disturbance on Francis St around 1am."

Anyone with any information is asked to contact Mr Evans at the Hamilton Central Police Station on 07 858 6200 or alternatively, information can be left anonymously with Crimestoppers on 0800 555111.

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