Staff working for Coca Cola in Invercargill have been warned to take care after the company fielded numerous phone calls from the partner of a woman whose death was linked to the product.
Christopher Hodgkinson's partner Natasha Harris died in 2010 after drinking up to eight litres of Coke a day for several years.
A coroner later said she wouldn't have died if it wasn't for her dependence on the fizzy drink.
Last week Mr Hodgkinson made several angry calls to the company asking for its help to get back custody of his children, reports Fairfax Media.
The company refused to comment directly about the calls but told Fairfax the company was absolutely committed to keeping its people safe.
Police also said they were "making inquiries into the matter".
"Police are aware of allegations that threatening phone calls were recently made to a group of people in a call centre," they told Fairfax.
Ms Harris was aged 30 when she died.