A reward offered by friends has helped a police investigation into the poisoning of a Northland man

Dave Davan from Herekino, near Kaitaia, died after drinking poisoned port from a bottle left in his letterbox, in December 2021.

A year after the 67-year-old's death, his brother Grant and friends put up a 42 thousand dollar reward for information leading to a conviction.

Police say more people came forward - and they're looking into the information given.