A hunt for information on two items left at the scene of Arthur Easton's murder almost 40 years ago

The Papakura man was stabbed to death in 1985 - and his family says unanswered questions have haunt them every day.

Alan Hall's wrongful conviction was only overturned after he'd been in jail 19 years.

Detective Inspector Warrick Adkin says they're offering a 100-thousand dollar reward - expiring on January 24 - for information leading to a conviction.

He says a woollen hat and bayonet were left behind by the killer.