Police are offering a $50,000 reward in the murder case of West Auckland man Brett Fraser.

Brett was killed on the night of Tuesday, October 21, at the warehouse property he shared with his flatmate in Westech Place, Glen Eden.

Brett Fraser was murdered in October last year.

Police believe the incident was motivated by a cannabis robbery.

Brett's flatmate was running a cannabis growing operation at the warehouse and had recently harvested his plants.

'At around 9.30pm that night, Brett's flatmate was upstairs and described hearing Brett call out to him. He began to come downstairs but as he did so he was assaulted by a man wearing a balaclava and holding a sharp object,” says Detective Inspector Bruce Scott.

He was then ordered back upstairs to show the offender where his cannabis was located.

He handed over the cannabis, but when he came back downstairs he found Brett injured on the floor.

Brett died at the scene after suffering a blunt-force injury to the top half of his body.

Over the past 10 months, detectives have pursued a wide range of enquiries, but sadly the majority of these possibilities have now been exhausted.

'Investigators have spoken at length with more than 50 people, including associates of Brett's and possible witnesses, but to date, no information has been found that would lead to the identification of the offender/s,” says Bruce.

'Lengthy enquiries were made into identifying and locating two men who were seen walking near the warehouse on the night of the murder, including the gathering and review of any available CCTV footage from the wider area, but to date, the men remain unidentified.”

Police are hoping the offer of a reward will prompt those with key information to come forward and offer this to investigators.

'We are determined to find whoever is responsible for Brett Fraser's death. Yes, he was living at a house where drugs were being grown, but no-one deserves to die on a cold warehouse floor at the hands of another, and no-one has the right to do this to another person,” explains Bruce.

'We are certain that there are people out there who know what happened last October and this may make them rethink their loyalties.”

The reward of up to $50,000 will be paid for material information or evidence, which leads to the identity and conviction of any person or persons responsible for the death of Brett Fraser.

Immunity against prosecution will be considered for any accomplice who gives information or evidence, but who is not the principle offender.

The reward is being offered until October 1.

Anyone with information is asked to contact Detective Sergeant Mike Clubb, Henderson Police on 09 839 0662 or email michael.clubb@police.govt.nz

Information can also be given anonymously via Crimestoppers on 0800 555 111.