Police called a press conference today to announce a 60-year-old man's been arrested in relation to threats to contaminate infant formula with 1080 poison.
Anonymous letters were sent to Fonterra and Federated Farmers last year along with small packages of milk powder laced with a concentrated form of 1080.
They contained threats to contaminate infant and other formula with the poison unless New Zealand stopped using 1080 for pest control by the end of March.
More than 50,000 tests failed to reveal any contamination.
Watch the video for the full press conference.