Fonterra is conducting an internal review but denies any wrongdoing after Chinese police arrested 19 people in Shanghai for selling around 300 tonnes of the company's expired milk powder.
The suspects were allegedly managing a company, which was packaging expired products of Fonterra - one of the most popular brands in China - into smaller packages for resale below market prices, according to the Shanghai Daily.
Fonterra spokeswoman Maree Wilson said none of the people arrested were Fonterra employees, contractors nor associated with the company.
"The exact details are unclear in the media reports we have seen to date," she said.
"Chinese officials have stated in the media that several different parties are allegedly involved in this case.