A food safety investigation has found a Nelson-based bacon company was the source of a listeria contamination that left four people sick.
Pestell's Rai Bacon Company's ham products were recalled from stores in Wellington and the across the South Island last month following fears they were contaminated.
The Ministry for Primary Industries said investigators traced the bug back to Pestell's and processing environment, confirming it was the source of the contaminated product.
The December recall prompted the company to cease producing and selling ready-to-eat ham products after testing by a customer identified listeria in products.